diff --git a/confiture-web-app/src/components/audit/AuditGenerationCriterium.vue b/confiture-web-app/src/components/audit/AuditGenerationCriterium.vue
index f4d40356..b6149172 100644
--- a/confiture-web-app/src/components/audit/AuditGenerationCriterium.vue
+++ b/confiture-web-app/src/components/audit/AuditGenerationCriterium.vue
@@ -119,7 +119,7 @@ function toggleTransverseComment() {
 
 const notify = useNotifications();
 
-const errorMessage: Ref<FileErrorMessage | null> = ref(null);
+const errorMessage: Ref<FileErrorMessage | string | null> = ref(null);
 const criteriumNotCompliantAccordion =
   ref<InstanceType<typeof CriteriumNotCompliantAccordion>>();
 
diff --git a/confiture-web-app/src/components/audit/CriteriumNotCompliantAccordion.vue b/confiture-web-app/src/components/audit/CriteriumNotCompliantAccordion.vue
index c544da97..55cb7320 100644
--- a/confiture-web-app/src/components/audit/CriteriumNotCompliantAccordion.vue
+++ b/confiture-web-app/src/components/audit/CriteriumNotCompliantAccordion.vue
@@ -14,7 +14,7 @@ import MarkdownHelpButton from "./MarkdownHelpButton.vue";
 export interface Props {
   id: string;
   comment: string | null;
-  errorMessage?: FileErrorMessage | null;
+  errorMessage?: FileErrorMessage | string | null;
   exampleImages: AuditFile[];
   quickWin?: boolean;
   userImpact: CriterionResultUserImpact | null;
diff --git a/confiture-web-app/src/components/audit/NotesModal.vue b/confiture-web-app/src/components/audit/NotesModal.vue
index 4042504c..fcd0c0e6 100644
--- a/confiture-web-app/src/components/audit/NotesModal.vue
+++ b/confiture-web-app/src/components/audit/NotesModal.vue
@@ -28,7 +28,7 @@ defineExpose({
   hide: () => modal.value?.hide()
 });
 
-const errorMessage: Ref<FileErrorMessage | null> = ref(null);
+const errorMessage: Ref<FileErrorMessage | string | null> = ref(null);
 const fileUpload = ref<InstanceType<typeof FileUpload>>();
 
 const auditStore = useAuditStore();
diff --git a/confiture-web-app/src/components/ui/FileUpload.vue b/confiture-web-app/src/components/ui/FileUpload.vue
index 2d80e179..05895812 100644
--- a/confiture-web-app/src/components/ui/FileUpload.vue
+++ b/confiture-web-app/src/components/ui/FileUpload.vue
@@ -10,7 +10,7 @@ import { formatBytes, getUploadUrl } from "../../utils";
 export interface Props {
   acceptedFormats?: Array<string>;
   auditFiles: AuditFile[];
-  errorMessage?: FileErrorMessage | null;
+  errorMessage?: FileErrorMessage | string | null;
   maxFileSize?: string;
   multiple?: boolean;
   readonly?: boolean;
diff --git a/confiture-web-app/src/utils.ts b/confiture-web-app/src/utils.ts
index 489943ec..868a3804 100644
--- a/confiture-web-app/src/utils.ts
+++ b/confiture-web-app/src/utils.ts
@@ -245,7 +245,7 @@ export async function handleFileUploadError(
   error: Error
 ): Promise<FileErrorMessage | string> {
   if (error instanceof HTTPError) {
-    let errorType: FileErrorMessage | null = null;
+    let errorType: FileErrorMessage;
     if (error.response.status === 413) {
       errorType = FileErrorMessage.UPLOAD_SIZE;
     }