diff --git a/application/Espo/Classes/FieldProcessing/Email/IcsDataLoader.php b/application/Espo/Classes/FieldProcessing/Email/IcsDataLoader.php
index 0d2ca389b0..b79cdcbb3b 100644
--- a/application/Espo/Classes/FieldProcessing/Email/IcsDataLoader.php
+++ b/application/Espo/Classes/FieldProcessing/Email/IcsDataLoader.php
@@ -91,6 +91,12 @@ class IcsDataLoader implements Loader
             return;
         }
 
+        $method = $ical->cal['VCALENDAR']['METHOD'] ?? null;
+
+        if ($method === 'REPLY') {
+            return;
+        }
+
         $espoEvent = EventFactory::createFromU01jmg3Ical($ical);
 
         $valueMap = (object) [
diff --git a/application/Espo/Core/Mail/Sender.php b/application/Espo/Core/Mail/Sender.php
index 356993b40e..26a6d9e5d3 100644
--- a/application/Espo/Core/Mail/Sender.php
+++ b/application/Espo/Core/Mail/Sender.php
@@ -31,6 +31,7 @@ namespace Espo\Core\Mail;
 
 use Espo\Core\FileStorage\Manager as FileStorageManager;
 use Espo\Core\Mail\Exceptions\NoSmtp;
+use Espo\Core\Mail\Sender\AttachmentContainer;
 use Espo\Core\Mail\Sender\MessageContainer;
 use Espo\Core\Mail\Sender\TransportPreparatorFactory;
 use Espo\Core\ORM\Repository\Option\SaveOption;
@@ -67,7 +68,7 @@ class Sender
     /** @var array<string, mixed> */
     private array $overrideParams = [];
     private ?string $envelopeFromAddress = null;
-    /** @var ?iterable<Attachment> */
+    /** @var ?iterable<Attachment|AttachmentContainer> */
     private $attachmentList = null;
     /** @var array{string, string}[] */
     private array $headers = [];
@@ -146,7 +147,7 @@ class Sender
     /**
      * With specific attachments.
      *
-     * @param iterable<Attachment> $attachmentList
+     * @param iterable<Attachment|AttachmentContainer> $attachmentList
      */
     public function withAttachments(iterable $attachmentList): self
     {
@@ -309,18 +310,23 @@ class Sender
             }
         }
 
+        /** @var AttachmentContainer[] $containers */
+        $containers = [];
+
         if ($this->attachmentList !== null) {
             foreach ($this->attachmentList as $attachment) {
-                $collection[] = $attachment;
+                if ($attachment instanceof Attachment) {
+                    $collection[] = $attachment;
+                } else {
+                    $containers[] = $attachment;
+                }
             }
         }
 
         $list = [];
 
         foreach ($collection as $attachment) {
-            $contents = $attachment->has(self::ATTACHMENT_ATTR_CONTENTS) ?
-                $attachment->get(self::ATTACHMENT_ATTR_CONTENTS) :
-                $this->fileStorageManager->getContents($attachment);
+            $contents = $this->getAttachmentContents($attachment);
 
             $part = new DataPart(
                 body: $contents,
@@ -331,6 +337,8 @@ class Sender
             $list[] = $part;
         }
 
+        $this->prepareContainerParts($containers, $list);
+
         return $list;
     }
 
@@ -342,9 +350,7 @@ class Sender
         $list = [];
 
         foreach ($email->getInlineAttachmentList() as $attachment) {
-            $contents = $attachment->has(self::ATTACHMENT_ATTR_CONTENTS) ?
-                $attachment->get(self::ATTACHMENT_ATTR_CONTENTS) :
-                $this->fileStorageManager->getContents($attachment);
+            $contents = $this->getAttachmentContents($attachment);
 
             $part = (new DataPart($contents, null, $attachment->getType()))
                 ->asInline()
@@ -541,4 +547,48 @@ class Sender
 
         return new Envelope(new Address($this->envelopeFromAddress), $recipients);
     }
+
+    /**
+     * @todo Use stream.
+     *
+     */
+    private function getAttachmentContents(Attachment $attachment): string
+    {
+        return $attachment->has(self::ATTACHMENT_ATTR_CONTENTS) ?
+            $attachment->get(self::ATTACHMENT_ATTR_CONTENTS) :
+            $this->fileStorageManager->getContents($attachment);
+    }
+
+    /**
+     * @param AttachmentContainer[] $containers
+     * @param DataPart[] $list
+     */
+    private function prepareContainerParts(array $containers, array &$list): void
+    {
+        foreach ($containers as $container) {
+            $attachment = $container->attachment;
+
+            $contents = $this->getAttachmentContents($attachment);
+
+            $part = new DataPart(
+                body: $contents,
+                filename: $attachment->getName() ?? '',
+                contentType: $attachment->getType(),
+            );
+
+            if ($container->inline) {
+                $part->asInline();
+            }
+
+            if ($container->contentTypeParams && $attachment->getType()) {
+                $part->getHeaders()->addParameterizedHeader(
+                    name: 'Content-Type',
+                    value: $attachment->getType(),
+                    params: $container->contentTypeParams,
+                );
+            }
+
+            $list[] = $part;
+        }
+    }
 }
diff --git a/application/Espo/Core/Mail/Sender/AttachmentContainer.php b/application/Espo/Core/Mail/Sender/AttachmentContainer.php
new file mode 100644
index 0000000000..ea251bd27b
--- /dev/null
+++ b/application/Espo/Core/Mail/Sender/AttachmentContainer.php
@@ -0,0 +1,51 @@
+<?php
+/************************************************************************
+ * This file is part of EspoCRM.
+ *
+ * EspoCRM – Open Source CRM application.
+ * Copyright (C) 2014-2026 EspoCRM, Inc.
+ * Website: https://www.espocrm.com
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program. If not, see <https://www.gnu.org/licenses/>.
+ *
+ * The interactive user interfaces in modified source and object code versions
+ * of this program must display Appropriate Legal Notices, as required under
+ * Section 5 of the GNU Affero General Public License version 3.
+ *
+ * In accordance with Section 7(b) of the GNU Affero General Public License version 3,
+ * these Appropriate Legal Notices must retain the display of the "EspoCRM" word.
+ ************************************************************************/
+
+namespace Espo\Core\Mail\Sender;
+
+use Espo\Entities\Attachment;
+
+/**
+ * @since 10.0.0
+ * @internal
+ */
+readonly class AttachmentContainer
+{
+    /**
+     * Important: Use named parameters. Parameter order backward compatibility is not guaranteed.
+     *
+     * @param Attachment $attachment
+     * @param array<string, string> $contentTypeParams
+     */
+    public function __construct(
+        public Attachment $attachment,
+        public bool $inline = false,
+        public array $contentTypeParams = [],
+    ) {}
+}
diff --git a/application/Espo/Modules/Crm/Business/Event/Ics.php b/application/Espo/Modules/Crm/Business/Event/Ics.php
index 300621a098..284fa5b52d 100644
--- a/application/Espo/Modules/Crm/Business/Event/Ics.php
+++ b/application/Espo/Modules/Crm/Business/Event/Ics.php
@@ -60,8 +60,8 @@ class Ics
 
     /**
      * @param array{
-     *     organizer?: array{string, ?string}|null,
-     *     attendees?: array{string, ?string}[],
+     *     organizer?: array{0: string, 1: ?string}|null,
+     *     attendees?: array{0: string, 1: ?string, 2: string|null}[],
      *     startDate?: ?int,
      *     endDate?: ?int,
      *     summary?: ?string,
@@ -115,7 +115,7 @@ class Ics
         $organizerPart = '';
 
         if ($this->organizer) {
-            $organizerPart = "ORGANIZER;{$this->preparePerson($this->organizer[0], $this->organizer[1])}";
+            $organizerPart = "ORGANIZER;{$this->preparePerson($this->organizer[0], $this->organizer[1], null)}";
         }
 
         $locationValuePart = $this->escapeString($this->formatMultiline($this->address));
@@ -136,7 +136,7 @@ class Ics
             "STATUS:$this->status\r\n";
 
         foreach ($this->attendees as $attendee) {
-            $body .= "ATTENDEE;{$this->preparePerson($attendee[0], $attendee[1])}";
+            $body .= "ATTENDEE;{$this->preparePerson($attendee[0], $attendee[1], $attendee[2] ?? null)}";
         }
 
         $end =
@@ -146,9 +146,17 @@ class Ics
         $this->output = $start . $body . $end;
     }
 
-    private function preparePerson(string $address, ?string $name): string
+    private function preparePerson(string $address, ?string $name, ?string $status): string
     {
-        return "CN={$this->escapeString($name)}:MAILTO:{$this->escapeString($address)}\r\n";
+        $output = '';
+
+        if ($status) {
+            $output .= "PARTSTAT=$status;";
+        }
+
+        $output .= "CN={$this->escapeString($name)}:MAILTO:{$this->escapeString($address)}\r\n";
+
+        return $output;
     }
 
     private function formatTimestamp(?int $timestamp): string
diff --git a/application/Espo/Modules/Crm/Business/Event/Invitations.php b/application/Espo/Modules/Crm/Business/Event/Invitations.php
index e5eb7c7d9e..af6004de70 100644
--- a/application/Espo/Modules/Crm/Business/Event/Invitations.php
+++ b/application/Espo/Modules/Crm/Business/Event/Invitations.php
@@ -32,6 +32,7 @@ namespace Espo\Modules\Crm\Business\Event;
 use Espo\Core\Field\DateTime as DateTimeField;
 use Espo\Core\Field\LinkParent;
 use Espo\Core\Mail\Exceptions\SendingError;
+use Espo\Core\Mail\Sender\AttachmentContainer;
 use Espo\Core\Name\Field;
 use Espo\Core\Utils\Config\ApplicationConfig;
 use Espo\Entities\Attachment;
@@ -166,8 +167,23 @@ class Invitations
             $sender->withSmtpParams($this->smtpParams);
         }
 
+        $method = 'REQUEST';
+
+        if ($type === self::TYPE_CANCELLATION) {
+            $method = 'CANCEL';
+        }
+
+        $container = new AttachmentContainer(
+            attachment: $attachment,
+            inline: true,
+            contentTypeParams: [
+                'charset' => 'utf-8',
+                'method' => $method,
+            ],
+        );
+
         $sender
-            ->withAttachments([$attachment])
+            ->withAttachments([$container])
             ->send($email);
     }
 
@@ -217,9 +233,9 @@ class Invitations
             $organizerName = $user->getName();
             $organizerAddress = $user->getEmailAddress();
 
-            if ($organizerAddress) {
+            /*if ($organizerAddress) {
                 $addressList[] = $organizerAddress;
-            }
+            }*/
         }
 
         $status = $type === self::TYPE_CANCELLATION ?
@@ -292,7 +308,7 @@ class Invitations
 
     /**
      * @param string[] $addressList
-     * @return array{string, ?string}[]
+     * @return array{string, ?string, ?string}[]
      */
     private function getAttendees(Meeting|Call $entity, array $addressList): array
     {
@@ -308,7 +324,7 @@ class Invitations
 
             if ($address && !in_array($address, $addressList)) {
                 $addressList[] = $address;
-                $attendees[] = [$address, $it->getName()];
+                $attendees[] = [$address, $it->getName(), $this->getStatus($it)];
             }
         }
 
@@ -322,7 +338,7 @@ class Invitations
 
             if ($address && !in_array($address, $addressList)) {
                 $addressList[] = $address;
-                $attendees[] = [$address, $it->getName()];
+                $attendees[] = [$address, $it->getName(), $this->getStatus($it)];
             }
         }
 
@@ -336,7 +352,7 @@ class Invitations
 
             if ($address && !in_array($address, $addressList)) {
                 $addressList[] = $address;
-                $attendees[] = [$address, $it->getName()];
+                $attendees[] = [$address, $it->getName(), $this->getStatus($it)];
             }
         }
 
@@ -391,4 +407,16 @@ class Invitations
 
         return $this->dateTime->convertSystemDateTime($value, $timeZone, $format, $language);
     }
+
+    private function getStatus(User|Contact|Lead $invitee): ?string
+    {
+        $status = $invitee->get('acceptanceStatus');
+
+        return match ($status) {
+            Meeting::ATTENDEE_STATUS_ACCEPTED => 'ACCEPTED',
+            Meeting::ATTENDEE_STATUS_DECLINED => 'DECLINED',
+            Meeting::ATTENDEE_STATUS_TENTATIVE => 'TENTATIVE',
+            default => null,
+        };
+    }
 }
diff --git a/application/Espo/Modules/Crm/Controllers/Call.php b/application/Espo/Modules/Crm/Controllers/Call.php
index 4e4c0a61b0..2e0b212673 100644
--- a/application/Espo/Modules/Crm/Controllers/Call.php
+++ b/application/Espo/Modules/Crm/Controllers/Call.php
@@ -53,7 +53,7 @@ class Call extends Record
      * @throws SendingError
      * @throws NotFound
      */
-    public function postActionSendInvitations(Request $request): bool
+    public function postActionSendInvitations(Request $request): stdClass
     {
         $id = $request->getParsedBody()->id ?? null;
 
@@ -63,11 +63,13 @@ class Call extends Record
 
         $invitees = $this->fetchInvitees($request);
 
-        $resultList = $this->injectableFactory
+        $sentToList = $this->injectableFactory
             ->create(InvitationService::class)
             ->send(CallEntity::ENTITY_TYPE, $id, $invitees);
 
-        return $resultList !== 0;
+        return (object) [
+            'idList' => array_map(fn ($it) => $it->getId() , $sentToList),
+        ];
     }
 
     /**
@@ -77,7 +79,7 @@ class Call extends Record
      * @throws SendingError
      * @throws NotFound
      */
-    public function postActionSendCancellation(Request $request): bool
+    public function postActionSendCancellation(Request $request): stdClass
     {
         $id = $request->getParsedBody()->id ?? null;
 
@@ -87,11 +89,13 @@ class Call extends Record
 
         $invitees = $this->fetchInvitees($request);
 
-        $resultList = $this->injectableFactory
+        $sentToList = $this->injectableFactory
             ->create(InvitationService::class)
             ->sendCancellation(CallEntity::ENTITY_TYPE, $id, $invitees);
 
-        return $resultList !== 0;
+        return (object) [
+            'idList' => array_map(fn ($it) => $it->getId() , $sentToList),
+        ];
     }
 
     /**
diff --git a/application/Espo/Modules/Crm/Controllers/Meeting.php b/application/Espo/Modules/Crm/Controllers/Meeting.php
index 68c54708ee..ad522570ce 100644
--- a/application/Espo/Modules/Crm/Controllers/Meeting.php
+++ b/application/Espo/Modules/Crm/Controllers/Meeting.php
@@ -53,7 +53,7 @@ class Meeting extends Record
      * @throws SendingError
      * @throws NotFound
      */
-    public function postActionSendInvitations(Request $request): bool
+    public function postActionSendInvitations(Request $request): stdClass
     {
         $id = $request->getParsedBody()->id ?? null;
 
@@ -63,11 +63,13 @@ class Meeting extends Record
 
         $invitees = $this->fetchInvitees($request);
 
-        $resultList = $this->injectableFactory
+        $sentToList = $this->injectableFactory
             ->create(InvitationService::class)
             ->send(MeetingEntity::ENTITY_TYPE, $id, $invitees);
 
-        return $resultList !== 0;
+        return (object) [
+            'idList' => array_map(fn ($it) => $it->getId() , $sentToList),
+        ];
     }
 
     /**
@@ -77,7 +79,7 @@ class Meeting extends Record
      * @throws SendingError
      * @throws NotFound
      */
-    public function postActionSendCancellation(Request $request): bool
+    public function postActionSendCancellation(Request $request): stdClass
     {
         $id = $request->getParsedBody()->id ?? null;
 
@@ -87,11 +89,13 @@ class Meeting extends Record
 
         $invitees = $this->fetchInvitees($request);
 
-        $resultList = $this->injectableFactory
+        $sentToList = $this->injectableFactory
             ->create(InvitationService::class)
             ->sendCancellation(MeetingEntity::ENTITY_TYPE, $id, $invitees);
 
-        return $resultList !== 0;
+        return (object) [
+            'idList' => array_map(fn ($it) => $it->getId() , $sentToList),
+        ];
     }
 
     /**
diff --git a/application/Espo/Modules/Crm/Resources/i18n/en_US/Meeting.json b/application/Espo/Modules/Crm/Resources/i18n/en_US/Meeting.json
index 7ecdfbd037..08aeee0723 100644
--- a/application/Espo/Modules/Crm/Resources/i18n/en_US/Meeting.json
+++ b/application/Espo/Modules/Crm/Resources/i18n/en_US/Meeting.json
@@ -59,6 +59,7 @@
         "sendInvitationsToSelectedAttendees": "Invitation emails will be sent to the selected attendees.",
         "sendCancellationsToSelectedAttendees": "Cancellation emails will be sent to the selected attendees.",
         "selectAcceptanceStatus": "Set your acceptance status.",
-        "nothingHasBeenSent": "Nothing were sent"
+        "nothingHasBeenSent": "Nothing were sent",
+        "invitationsSentTo": "Invitation emails has been sent to: {recipients}.\n\nCould not sent to: {failedRecipients}."
     }
 }
diff --git a/application/Espo/Modules/Crm/Tools/Meeting/Invitation/Sender.php b/application/Espo/Modules/Crm/Tools/Meeting/Invitation/Sender.php
index 15adba032b..ab903ec228 100644
--- a/application/Espo/Modules/Crm/Tools/Meeting/Invitation/Sender.php
+++ b/application/Espo/Modules/Crm/Tools/Meeting/Invitation/Sender.php
@@ -34,24 +34,28 @@ use Espo\Core\Exceptions\Forbidden;
 use Espo\Core\InjectableFactory;
 use Espo\Core\Mail\Exceptions\SendingError;
 use Espo\Core\Mail\SmtpParams;
-use Espo\Core\Name\Field;
 use Espo\Core\Utils\Config;
+use Espo\Core\Utils\Log;
 use Espo\Core\Utils\Metadata;
 use Espo\Entities\User;
 use Espo\Modules\Crm\Business\Event\Invitations;
 use Espo\Modules\Crm\Entities\Call;
+use Espo\Modules\Crm\Entities\Contact;
+use Espo\Modules\Crm\Entities\Lead;
 use Espo\Modules\Crm\Entities\Meeting;
 use Espo\ORM\Entity;
 use Espo\ORM\EntityManager;
+use Espo\ORM\Repository\RDBRelation;
 use Espo\Tools\Email\SendService;
+use LogicException;
 
 /**
  * @since 9.0.0
  */
 class Sender
 {
-    private const TYPE_INVITATION = 'invitation';
-    private const TYPE_CANCELLATION = 'cancellation';
+    private const string TYPE_INVITATION = 'invitation';
+    private const string TYPE_CANCELLATION = 'cancellation';
 
     public function __construct(
         private SendService $sendService,
@@ -60,6 +64,7 @@ class Sender
         private EntityManager $entityManager,
         private Config $config,
         private Metadata $metadata,
+        private Log $log,
     ) {}
 
     /**
@@ -86,29 +91,22 @@ class Sender
         return $this->sendInternal($entity, self::TYPE_CANCELLATION, $targets);
     }
 
-
     /**
      * @param ?Invitee[] $targets
-     * @return Entity[]
-     * @throws SendingError
-     * @throws Forbidden
+     * @return (User|Contact|Lead)[]
      */
-    private function sendInternal(Meeting|Call $entity, string $type, ?array $targets): array
+    private function getRecipients(Meeting|Call $entity, string $type, ?array $targets): array
     {
-        $this->checkStatus($entity, $type);
-
         $linkList = [
             Meeting::LINK_USERS,
             Meeting::LINK_CONTACTS,
             Meeting::LINK_LEADS,
         ];
 
-        $sender = $this->getSender();
-
-        $sentAddressList = [];
-        $resultEntityList = [];
+        $output = [];
 
         foreach ($linkList as $link) {
+            /** @var RDBRelation<User>|RDBRelation<Contact>|RDBRelation<Lead> $builder */
             $builder = $this->entityManager->getRelation($entity, $link);
 
             if ($targets === null && $type === self::TYPE_INVITATION) {
@@ -118,7 +116,7 @@ class Sender
             $collection = $builder->find();
 
             foreach ($collection as $attendee) {
-                $emailAddress = $attendee->get(Field::EMAIL_ADDRESS);
+                $emailAddress = $attendee->getEmailAddress();
 
                 if ($targets) {
                     $target = self::findTarget($attendee, $targets);
@@ -132,10 +130,60 @@ class Sender
                     }
                 }
 
-                if (!$emailAddress || in_array($emailAddress, $sentAddressList)) {
+                if (!$emailAddress) {
                     continue;
                 }
 
+                $output[] = $attendee;
+            }
+        }
+
+        return $output;
+    }
+
+    /**
+     * @param ?Invitee[] $targets
+     * @return Entity[]
+     * @throws SendingError
+     * @throws Forbidden
+     */
+    private function sendInternal(Meeting|Call $entity, string $type, ?array $targets): array
+    {
+        $this->checkStatus($entity, $type);
+
+        $sender = $this->getSender();
+
+        $sentAddressList = [];
+        $resultEntityList = [];
+
+        $recipients = $this->getRecipients($entity, $type, $targets);
+
+        foreach ($recipients as $recipient) {
+            $link = $this->getLinkName($recipient);
+
+            $this->entityManager
+                ->getRelation($entity, $link)
+                ->updateColumns($recipient, ['status' => Meeting::ATTENDEE_STATUS_NONE]);
+        }
+
+        foreach ($recipients as $attendee) {
+            $emailAddress = $attendee->getEmailAddress();
+
+            $link = $this->getLinkName($attendee);
+
+            if ($targets) {
+                $target = self::findTarget($attendee, $targets);
+
+                if ($target?->getEmailAddress()) {
+                    $emailAddress = $target->getEmailAddress();
+                }
+            }
+
+            if (!$emailAddress || in_array($emailAddress, $sentAddressList)) {
+                continue;
+            }
+
+            try {
                 if ($type === self::TYPE_INVITATION) {
                     $sender->sendInvitation($entity, $attendee, $link, $emailAddress);
                 }
@@ -143,14 +191,18 @@ class Sender
                 if ($type === self::TYPE_CANCELLATION) {
                     $sender->sendCancellation($entity, $attendee, $link, $emailAddress);
                 }
+            } catch (SendingError $e) {
+                $this->log->error("Could not send event invitation to {entityType} {id}.", [
+                    'exception' => $e,
+                    'entityType' => $attendee->getEntityType(),
+                    'id' => $attendee->getId(),
+                ]);
 
-                $sentAddressList[] = $emailAddress;
-                $resultEntityList[] = $attendee;
-
-                $this->entityManager
-                    ->getRelation($entity, $link)
-                    ->updateColumns($attendee, ['status' => Meeting::ATTENDEE_STATUS_NONE]);
+                continue;
             }
+
+            $sentAddressList[] = $emailAddress;
+            $resultEntityList[] = $attendee;
         }
 
         return $resultEntityList;
@@ -220,4 +272,15 @@ class Sender
     {
         return $this->metadata->get("scopes.$entityType.canceledStatusList") ?? [];
     }
+
+    private function getLinkName(User|Contact|Lead $recipient): string
+    {
+        $linkMap = [
+            User::ENTITY_TYPE => Meeting::LINK_USERS,
+            Contact::ENTITY_TYPE => Meeting::LINK_CONTACTS,
+            Lead::ENTITY_TYPE => Meeting::LINK_LEADS,
+        ];
+
+        return $linkMap[$recipient::ENTITY_TYPE] ?? throw new LogicException();
+    }
 }
diff --git a/client/modules/crm/src/views/meeting/modals/send-invitations.js b/client/modules/crm/src/views/meeting/modals/send-invitations.js
index 93eefc76ca..562abd0a4a 100644
--- a/client/modules/crm/src/views/meeting/modals/send-invitations.js
+++ b/client/modules/crm/src/views/meeting/modals/send-invitations.js
@@ -30,6 +30,7 @@ import Utils from 'utils';
 import ModalView from 'views/modal';
 import Collection from 'collection';
 import Ajax from 'ajax';
+import Ui from 'ui';
 
 export default class SendInvitationsModalView extends ModalView {
 
@@ -167,25 +168,45 @@ export default class SendInvitationsModalView extends ModalView {
 
         Espo.Ui.notifyWait();
 
-        const targets = this.getListView().checkedList.map(id => {
-            return {
-                entityType: this.collection.get(id).entityType,
-                id: id,
-            };
-        });
+        const targets = this.getListView().getCheckedIds()
+            .map(id => this.collection.get(id));
 
         Ajax
             .postRequest(`${this.model.entityType}/action/sendInvitations`, {
                 id: this.model.id,
-                targets: targets,
+                targets: targets.map(m => {
+                    return {
+                        entityType: m.entityType,
+                        id: m.id,
+                    }
+                }),
             })
-            .then(result => {
-                result ?
-                    Espo.Ui.success(this.translate('Sent')) :
-                    Espo.Ui.warning(this.translate('nothingHasBeenSent', 'messages', 'Meeting'));
+            .then(/** {idList: string[]} */result => {
+                if (result.idList.length === 0) {
+                    Ui.warning(this.translate('nothingHasBeenSent', 'messages', 'Meeting'));
+                } else if (result.idList.length === targets.length) {
+                    Ui.success(this.translate('Sent'));
+                } else {
+                    const recipientsString = targets
+                        .filter(m => result.idList.includes(m.id))
+                        .map(m => m.attributes.name ?? m.attributes.id)
+                        .join(', ');
+
+                    const failedRecipientsString = targets
+                        .filter(m => !result.idList.includes(m.id))
+                        .map(m => m.attributes.name ?? m.attributes.id)
+                        .join(', ');
+
+                    const message = this.translate('invitationsSentTo', 'messages', 'Meeting')
+                        .replace('{recipients}', recipientsString)
+                        .replace('{failedRecipients}', failedRecipientsString);
+
+                    Ui.notify(message, 'warning', null, {
+                        closeButton: true,
+                    });
+                }
 
                 this.trigger('sent');
-
                 this.close();
             })
             .catch(() => {
diff --git a/tests/unit/Espo/Tools/Meeting/IcsTest.php b/tests/unit/Espo/Tools/Meeting/IcsTest.php
index 9454f59e1f..9430fe551b 100644
--- a/tests/unit/Espo/Tools/Meeting/IcsTest.php
+++ b/tests/unit/Espo/Tools/Meeting/IcsTest.php
@@ -47,7 +47,7 @@ class IcsTest extends TestCase
             'description' => 'Test.',
             'stamp' => strtotime('2025-01-01 09:00:00'),
             'attendees' => [
-                ['att1@test.com', 'Att 1'],
+                ['att1@test.com', 'Att 1', 'TENTATIVE'],
                 ['att2@test.com', 'Att 2'],
             ],
         ]);
@@ -67,7 +67,7 @@ class IcsTest extends TestCase
             "SEQUENCE:0\r\n".
             "DTSTAMP:20250101T090000Z\r\n".
             "STATUS:CONFIRMED\r\n".
-            "ATTENDEE;CN=Att 1:MAILTO:att1@test.com\r\n".
+            "ATTENDEE;PARTSTAT=TENTATIVE;CN=Att 1:MAILTO:att1@test.com\r\n".
             "ATTENDEE;CN=Att 2:MAILTO:att2@test.com\r\n".
             "END:VEVENT\r\n".
             "END:VCALENDAR";