diff --git a/backend/src/main/java/org/raddatz/familienarchiv/exception/ErrorCode.java b/backend/src/main/java/org/raddatz/familienarchiv/exception/ErrorCode.java
index 46ad1cd0..07751700 100644
--- a/backend/src/main/java/org/raddatz/familienarchiv/exception/ErrorCode.java
+++ b/backend/src/main/java/org/raddatz/familienarchiv/exception/ErrorCode.java
@@ -30,6 +30,8 @@ public enum ErrorCode {
     // --- Users ---
     /** A user with the given ID or username does not exist. 404 */
     USER_NOT_FOUND,
+    /** A group with the given ID does not exist. 404 */
+    GROUP_NOT_FOUND,
     /** The supplied email address is already used by another account. 409 */
     EMAIL_ALREADY_IN_USE,
     /** The supplied current password does not match the stored hash. 400 */
diff --git a/frontend/messages/de.json b/frontend/messages/de.json
index 727995da..3d659240 100644
--- a/frontend/messages/de.json
+++ b/frontend/messages/de.json
@@ -704,6 +704,7 @@
 	"error_invite_revoked": "Dieser Einladungslink wurde deaktiviert.",
 	"error_invite_expired": "Dieser Einladungslink ist abgelaufen.",
 	"error_group_has_active_invites": "Diese Gruppe kann nicht gelöscht werden, da sie in einer aktiven Einladung verwendet wird.",
+	"error_group_not_found": "Die angegebene Gruppe existiert nicht.",
 	"register_heading": "Konto erstellen",
 	"register_subtext": "Du wurdest eingeladen, dem Familienarchiv beizutreten.",
 	"register_label_first_name": "Vorname",
diff --git a/frontend/messages/en.json b/frontend/messages/en.json
index 7bbc2ad2..13c4168c 100644
--- a/frontend/messages/en.json
+++ b/frontend/messages/en.json
@@ -704,6 +704,7 @@
 	"error_invite_revoked": "This invite link has been deactivated.",
 	"error_invite_expired": "This invite link has expired.",
 	"error_group_has_active_invites": "This group cannot be deleted because it is referenced by one or more active invite links.",
+	"error_group_not_found": "The specified group does not exist.",
 	"register_heading": "Create account",
 	"register_subtext": "You've been invited to join Familienarchiv.",
 	"register_label_first_name": "First name",
diff --git a/frontend/messages/es.json b/frontend/messages/es.json
index aa5516d1..fb3fce97 100644
--- a/frontend/messages/es.json
+++ b/frontend/messages/es.json
@@ -704,6 +704,7 @@
 	"error_invite_revoked": "Este enlace de invitación ha sido desactivado.",
 	"error_invite_expired": "Este enlace de invitación ha expirado.",
 	"error_group_has_active_invites": "Este grupo no puede eliminarse porque está referenciado por uno o más enlaces de invitación activos.",
+	"error_group_not_found": "El grupo especificado no existe.",
 	"register_heading": "Crear cuenta",
 	"register_subtext": "Has sido invitado a unirte al Familienarchiv.",
 	"register_label_first_name": "Nombre",
diff --git a/frontend/src/lib/shared/errors.ts b/frontend/src/lib/shared/errors.ts
index 011be07e..9703bbd9 100644
--- a/frontend/src/lib/shared/errors.ts
+++ b/frontend/src/lib/shared/errors.ts
@@ -23,6 +23,7 @@ export type ErrorCode =
 	| 'INVITE_REVOKED'
 	| 'INVITE_EXPIRED'
 	| 'GROUP_HAS_ACTIVE_INVITES'
+	| 'GROUP_NOT_FOUND'
 	| 'ANNOTATION_NOT_FOUND'
 	| 'ANNOTATION_UPDATE_FAILED'
 	| 'TRANSCRIPTION_BLOCK_NOT_FOUND'
@@ -111,6 +112,8 @@ export function getErrorMessage(code: ErrorCode | string | undefined): string {
 			return m.error_invite_expired();
 		case 'GROUP_HAS_ACTIVE_INVITES':
 			return m.error_group_has_active_invites();
+		case 'GROUP_NOT_FOUND':
+			return m.error_group_not_found();
 		case 'ANNOTATION_NOT_FOUND':
 			return m.error_annotation_not_found();
 		case 'ANNOTATION_UPDATE_FAILED':