diff --git a/src/lib/server/db/file.ts b/src/lib/server/db/file.ts
index 0a76b6d..db450c7 100644
--- a/src/lib/server/db/file.ts
+++ b/src/lib/server/db/file.ts
@@ -163,16 +163,24 @@ export const unregisterDirectory = async (userId: number, directoryId: number) =
     .setIsolationLevel("repeatable read") // TODO: Sufficient?
     .execute(async (trx) => {
       const unregisterFiles = async (parentId: number) => {
-        return await trx
+        const files = await trx
+          .selectFrom("file")
+          .leftJoin("thumbnail", "file.id", "thumbnail.file_id")
+          .select(["file.id", "file.path", "thumbnail.path as thumbnailPath"])
+          .where("file.parent_id", "=", parentId)
+          .where("file.user_id", "=", userId)
+          .forUpdate("file")
+          .execute();
+        await trx
           .deleteFrom("file")
           .where("parent_id", "=", parentId)
           .where("user_id", "=", userId)
-          .returning(["id", "path"])
           .execute();
+        return files;
       };
       const unregisterDirectoryRecursively = async (
         directoryId: number,
-      ): Promise<{ id: number; path: string }[]> => {
+      ): Promise<{ id: number; path: string; thumbnailPath: string | null }[]> => {
         const files = await unregisterFiles(directoryId);
         const subDirectories = await trx
           .selectFrom("directory")
@@ -417,16 +425,22 @@ export const setFileEncName = async (
 };
 
 export const unregisterFile = async (userId: number, fileId: number) => {
-  const file = await db
-    .deleteFrom("file")
-    .where("id", "=", fileId)
-    .where("user_id", "=", userId)
-    .returning("path")
-    .executeTakeFirst();
-  if (!file) {
-    throw new IntegrityError("File not found");
-  }
-  return { path: file.path };
+  return await db.transaction().execute(async (trx) => {
+    const file = await trx
+      .selectFrom("file")
+      .leftJoin("thumbnail", "file.id", "thumbnail.file_id")
+      .select(["file.path", "thumbnail.path as thumbnailPath"])
+      .where("file.id", "=", fileId)
+      .where("file.user_id", "=", userId)
+      .forUpdate("file")
+      .executeTakeFirst();
+    if (!file) {
+      throw new IntegrityError("File not found");
+    }
+
+    await trx.deleteFrom("file").where("id", "=", fileId).execute();
+    return file;
+  });
 };
 
 export const addFileToCategory = async (fileId: number, categoryId: number) => {
diff --git a/src/lib/server/db/media.ts b/src/lib/server/db/media.ts
index 360ed49..8386ffc 100644
--- a/src/lib/server/db/media.ts
+++ b/src/lib/server/db/media.ts
@@ -37,7 +37,7 @@ export const updateFileThumbnail = async (
 
     const thumbnail = await trx
       .selectFrom("thumbnail")
-      .select("path as old_path")
+      .select("path as oldPath")
       .where("file_id", "=", fileId)
       .limit(1)
       .forUpdate()
@@ -60,7 +60,7 @@ export const updateFileThumbnail = async (
         }),
       )
       .execute();
-    return thumbnail?.old_path;
+    return thumbnail?.oldPath ?? null;
   });
 };
 
diff --git a/src/lib/server/services/directory.ts b/src/lib/server/services/directory.ts
index 2525069..fdab587 100644
--- a/src/lib/server/services/directory.ts
+++ b/src/lib/server/services/directory.ts
@@ -34,12 +34,19 @@ export const getDirectoryInformation = async (userId: number, directoryId: Direc
   };
 };
 
+const safeUnlink = async (path: string | null) => {
+  if (path) {
+    await unlink(path).catch(console.error);
+  }
+};
+
 export const deleteDirectory = async (userId: number, directoryId: number) => {
   try {
     const files = await unregisterDirectory(userId, directoryId);
     return {
-      files: files.map(({ id, path }) => {
-        unlink(path); // Intended
+      files: files.map(({ id, path, thumbnailPath }) => {
+        safeUnlink(path); // Intended
+        safeUnlink(thumbnailPath); // Intended
         return id;
       }),
     };
diff --git a/src/lib/server/services/file.ts b/src/lib/server/services/file.ts
index 6f5af03..0e20676 100644
--- a/src/lib/server/services/file.ts
+++ b/src/lib/server/services/file.ts
@@ -45,10 +45,17 @@ export const getFileInformation = async (userId: number, fileId: number) => {
   };
 };
 
+const safeUnlink = async (path: string | null) => {
+  if (path) {
+    await unlink(path).catch(console.error);
+  }
+};
+
 export const deleteFile = async (userId: number, fileId: number) => {
   try {
-    const { path } = await unregisterFile(userId, fileId);
-    unlink(path); // Intended
+    const { path, thumbnailPath } = await unregisterFile(userId, fileId);
+    safeUnlink(path); // Intended
+    safeUnlink(thumbnailPath); // Intended
   } catch (e) {
     if (e instanceof IntegrityError && e.message === "File not found") {
       error(404, "Invalid file id");
@@ -126,9 +133,7 @@ export const uploadFileThumbnail = async (
     await pipeline(encContentStream, createWriteStream(path, { flags: "wx", mode: 0o600 }));
 
     const oldPath = await updateFileThumbnail(userId, fileId, dekVersion, path, encContentIv);
-    if (oldPath) {
-      safeUnlink(oldPath); // Intended
-    }
+    safeUnlink(oldPath); // Intended
   } catch (e) {
     await safeUnlink(path);
 
@@ -157,10 +162,6 @@ export const scanMissingFileThumbnails = async (userId: number) => {
   return { files: fileIds };
 };
 
-const safeUnlink = async (path: string) => {
-  await unlink(path).catch(console.error);
-};
-
 export const uploadFile = async (
   params: Omit<NewFile, "path" | "encContentHash">,
   encContentStream: Readable,
diff --git a/src/routes/(main)/directory/[[id]]/service.svelte.ts b/src/routes/(main)/directory/[[id]]/service.svelte.ts
index d4a0556..b29630a 100644
--- a/src/routes/(main)/directory/[[id]]/service.svelte.ts
+++ b/src/routes/(main)/directory/[[id]]/service.svelte.ts
@@ -2,7 +2,13 @@ import { getContext, setContext } from "svelte";
 import { callGetApi, callPostApi } from "$lib/hooks";
 import { storeHmacSecrets } from "$lib/indexedDB";
 import { generateDataKey, wrapDataKey, unwrapHmacSecret, encryptString } from "$lib/modules/crypto";
-import { storeFileCache, deleteFileCache, storeFileThumbnail, uploadFile } from "$lib/modules/file";
+import {
+  storeFileCache,
+  deleteFileCache,
+  storeFileThumbnail,
+  deleteFileThumbnail,
+  uploadFile,
+} from "$lib/modules/file";
 import type {
   DirectoryRenameRequest,
   DirectoryCreateRequest,
@@ -114,10 +120,12 @@ export const requestEntryDeletion = async (entry: SelectedEntry) => {
 
   if (entry.type === "directory") {
     const { deletedFiles }: DirectoryDeleteResponse = await res.json();
-    await Promise.all(deletedFiles.map(deleteFileCache));
+    await Promise.all(
+      deletedFiles.flatMap((fileId) => [deleteFileCache(fileId), deleteFileThumbnail(fileId)]),
+    );
     return true;
   } else {
-    await deleteFileCache(entry.id);
+    await Promise.all([deleteFileCache(entry.id), deleteFileThumbnail(entry.id)]);
     return true;
   }
 };