diff --git a/src/frontend/public/locales/common/en-US.json b/src/frontend/public/locales/common/en-US.json
index 5ee807ce..1e9bc98f 100644
--- a/src/frontend/public/locales/common/en-US.json
+++ b/src/frontend/public/locales/common/en-US.json
@@ -136,7 +136,6 @@
   "Failed to refresh summary.": "Failed to refresh summary.",
   "Failed to save template. Please try again.": "Failed to save template. Please try again.",
   "Feedback?": "Feedback?",
-  "File too large": "File too large",
   "First name": "First name",
   "First name is required.": "First name is required.",
   "First, we need some information about your old mailbox": "First, we need some information about your old mailbox",
@@ -300,7 +299,6 @@
   "The domain <strong>{{domain}}</strong> has been created successfully.": "The domain <strong>{{domain}}</strong> has been created successfully.",
   "The email {{email}} is invalid.": "The email {{email}} is invalid.",
   "The email address is invalid.": "The email address is invalid.",
-  "The file is too large. It must be less than {{size}}.": "The file is too large. It must be less than {{size}}.",
   "The forced signature will be the only one usable for new messages.": "The forced signature will be the only one usable for new messages.",
   "The message could not be sent.": "The message could not be sent.",
   "The message could not be sent. Please try again later.": "The message could not be sent. Please try again later.",
diff --git a/src/frontend/public/locales/common/fr-FR.json b/src/frontend/public/locales/common/fr-FR.json
index 9e7539e7..669ef461 100644
--- a/src/frontend/public/locales/common/fr-FR.json
+++ b/src/frontend/public/locales/common/fr-FR.json
@@ -53,6 +53,7 @@
   "At least one recipient is required.": "Il faut au moins un destinataire.",
   "Attachment failed to be saved into your Drive's workspace.": "Impossible de sauvegarder la pièce jointe dans votre espace de travail Fichiers.",
   "Attachment saved into your Drive's workspace.": "Pièce jointe sauvegardée dans votre espace de travail Fichiers.",
+  "Attachment size limit exceeded": "La taille des pièces jointes excède la limite autorisée.",
   "Attachments must be less than {{size}}.": "Les pièces jointes ne peuvent pas excéder {{size}}.",
   "Authentication failed. Please check your credentials and ensure you have enabled IMAP connections in your account.": "L'authentification a échoué. Veuillez vérifier vos identifiants et assurez-vous d'avoir autorisé les connexions IMAP dans votre compte.",
   "Auto-labeling": "Labellisation automatique",
@@ -62,6 +63,7 @@
   "BCC: ": "CCI : ",
   "Blind copy: ": "Copie cachée : ",
   "Cancel": "Annuler",
+  "Cannot add attachment(s). Total size would be more than {{maxSize}}.": "Impossible d'ajouter ces pièces jointes. La taille totale dépasserait la limite autorisée de {{maxSize}}.",
   "Check DNS again": "Revérifier les DNS",
   "Checking DNS records...": "Vérification des enregistrements DNS...",
   "Close": "Fermer",
@@ -297,7 +299,6 @@
   "The domain <strong>{{domain}}</strong> has been created successfully.": "Le domaine <strong>{{domain}}</strong> a été créé avec succès.",
   "The email {{email}} is invalid.": "Le courriel {{email}} est invalide.",
   "The email address is invalid.": "L'adresse email est invalide.",
-  "The file is too large. It must be less than {{size}}.": "Le fichier est trop volumineux. Il doit être inférieur à {{size}}.",
   "The forced signature will be the only one usable for new messages.": "La signature forcée sera la seule utilisable pour les nouveaux messages.",
   "The message could not be sent.": "Le message n'a pas pu être envoyé.",
   "The message could not be sent. Please try again later.": "Le message n'a pas pu être envoyé. Veuillez réessayer plus tard.",
diff --git a/src/frontend/src/features/forms/components/message-form/attachment-uploader.tsx b/src/frontend/src/features/forms/components/message-form/attachment-uploader.tsx
index 789fe654..f53f21ed 100644
--- a/src/frontend/src/features/forms/components/message-form/attachment-uploader.tsx
+++ b/src/frontend/src/features/forms/components/message-form/attachment-uploader.tsx
@@ -5,7 +5,7 @@ import { useMailboxContext } from '@/features/providers/mailbox';
 import { useConfig } from '@/features/providers/config';
 import { useFormContext } from 'react-hook-form';
 import { Button, Field, useModals, VariantType } from '@openfun/cunningham-react';
-import { AttachmentItem } from '@/features/layouts/components/thread-view/components/thread-attachment-list/attachment-item';
+import { AttachmentItem, isAttachment } from '@/features/layouts/components/thread-view/components/thread-attachment-list/attachment-item';
 import { useTranslation } from 'react-i18next';
 import { useDropzone } from 'react-dropzone';
 import { AttachmentHelper } from '@/features/utils/attachment-helper';
@@ -39,7 +39,10 @@ export const AttachmentUploader = ({
     const debouncedOnChange = useDebounceCallback(onChange, 1000);
 
     // Calculate current total size of attachments and pending uploads
-    const attachmentsSize = attachments.reduce((acc, attachment) => acc + attachment.size, 0);
+    const attachmentsSize = attachments.reduce((acc, attachment) => {
+        if (isAttachment(attachment)) return acc + attachment.size;
+        return acc;
+    }, 0);
     const uploadingQueueSize = uploadingQueue.reduce((acc, file) => acc + file.size, 0);
     const currentTotalSize = attachmentsSize + uploadingQueueSize;
 
@@ -181,7 +184,9 @@ export const AttachmentUploader = ({
                             ? t("{{count}} attachments", { count: attachments.length, defaultValue_one: "{{count}} attachment" })
                             : t("No attachments")}
                         </strong>{' '}
-                        ({AttachmentHelper.getFormattedTotalSize(attachments, i18n.resolvedLanguage)})
+                        {attachments.filter(isAttachment).length > 0 && (
+                            `(${AttachmentHelper.getFormattedTotalSize(attachments.filter(isAttachment), i18n.resolvedLanguage)})`
+                        )}
                     </p>
                     <div className="attachment-bucket__list">
                         {failedQueue.map((entry) => (
diff --git a/src/frontend/src/features/layouts/components/thread-view/components/thread-attachment-list/attachment-item.tsx b/src/frontend/src/features/layouts/components/thread-view/components/thread-attachment-list/attachment-item.tsx
index bd27b27c..fc154669 100644
--- a/src/frontend/src/features/layouts/components/thread-view/components/thread-attachment-list/attachment-item.tsx
+++ b/src/frontend/src/features/layouts/components/thread-view/components/thread-attachment-list/attachment-item.tsx
@@ -19,10 +19,10 @@ type AttachmentItemProps = {
     onDelete?: () => void;
 }
 
-const isAttachment = (attachment: Attachment | File | DriveFile): attachment is Attachment => {
+export const isAttachment = (attachment: Attachment | File | DriveFile): attachment is Attachment => {
     return 'blobId' in attachment;
 }
-const isDriveFile = (attachment: Attachment | File | DriveFile): attachment is DriveFile => {
+export const isDriveFile = (attachment: Attachment | File | DriveFile): attachment is DriveFile => {
     return 'url' in attachment;
 }