diff --git a/Riot/Modules/Room/ParticipantsInviteModal/ContactsPicker/ContactsPickerViewModel.swift b/Riot/Modules/Room/ParticipantsInviteModal/ContactsPicker/ContactsPickerViewModel.swift
index aa1eb92ad7..ba73bea30f 100644
--- a/Riot/Modules/Room/ParticipantsInviteModal/ContactsPicker/ContactsPickerViewModel.swift
+++ b/Riot/Modules/Room/ParticipantsInviteModal/ContactsPicker/ContactsPickerViewModel.swift
@@ -291,7 +291,14 @@ extension ContactsPickerViewModel: ContactsTableViewControllerDelegate {
                         if let error = response.error as NSError?, error.domain == kMXRestClientErrorDomain, error.code == MXRestClientErrorMissingIdentityServer {
                             self.coordinatorDelegate?.contactsPickerViewModel(self, inviteFailedWithError: nil)
                             AppDelegate.theDelegate().showAlert(withTitle: VectorL10n.errorInvite3pidWithNoIdentityServer, message: nil)
-                        } else {
+                        }
+                        // Tchap: make error message clearer and in french when a member can't be invited to a room
+                        else if let mxError = MXError(nsError: response.error),
+                           mxError.errcode == kMXErrCodeStringForbidden,
+                           let tchapErrorCannotInvite = MXError(errorCode: mxError.errcode, error: TchapL10n.roomInviteErrorActionForbidden, userInfo: mxError.userInfo) {
+                            self.coordinatorDelegate?.contactsPickerViewModel(self, inviteFailedWithError: tchapErrorCannotInvite.createNSError())
+                        }
+                        else {
                             self.coordinatorDelegate?.contactsPickerViewModel(self, inviteFailedWithError: response.error)
                         }
                     }
diff --git a/changelog.d/908.change b/changelog.d/908.change
new file mode 100644
index 0000000000..73b6c94097
--- /dev/null
+++ b/changelog.d/908.change
@@ -0,0 +1 @@
+Message d'erreur en FR lors de l'échec d'invitation dans un salon d'un externe non présent dans l'annuaire
\ No newline at end of file