diff --git a/tdrive/backend/node/src/services/applications-api/index.ts b/tdrive/backend/node/src/services/applications-api/index.ts
index 312566cb..d817e62a 100644
--- a/tdrive/backend/node/src/services/applications-api/index.ts
+++ b/tdrive/backend/node/src/services/applications-api/index.ts
@@ -14,6 +14,11 @@ export default class ApplicationsApiService extends TdriveService<undefined> {
   version = "1";
   name = "applicationsapi";
 
+  private static default: ApplicationsApiService;
+  public static getDefault() {
+    return this.default;
+  }
+
   public async doInit(): Promise<this> {
     const fastify = this.context.getProvider<WebServerAPI>("webserver").getServer();
     fastify.register((instance, _opts, next) => {
@@ -70,10 +75,23 @@ export default class ApplicationsApiService extends TdriveService<undefined> {
         }
       }
     }
-
+    ApplicationsApiService.default = this;
     return this;
   }
 
+  /** Get the configuration of a given `appId` or `undefined` if unknown */
+  public getApplicationConfig(appId: string) {
+    const apps = config.get<Application[]>("applications.plugins") || [];
+    return apps.find(app => app.id === appId);
+  }
+
+  /** Get the configuration of a given `appId` or throw an error if unknown */
+  public requireApplicationConfig(appId: string) {
+    const app = this.getApplicationConfig(appId);
+    if (!app) throw new Error(`Unknown application.id ${JSON.stringify(appId)}`);
+    return app;
+  }
+
   /** Send a request to the plugin by its application id
    * @param url Full URL that doesn't start with a `/`
    */
@@ -82,9 +100,7 @@ export default class ApplicationsApiService extends TdriveService<undefined> {
     url: string,
     appId: string,
   ) {
-    const apps = config.get<Application[]>("applications.plugins") || [];
-    const app = apps.find(app => app.id === appId);
-    if (!app) throw new Error(`Unknown application.id ${JSON.stringify(appId)}`);
+    const app = this.requireApplicationConfig(appId);
     if (!app.internal_domain)
       throw new Error(`application.id ${JSON.stringify(appId)} missing an internal_domain`);
     const signature = jwt.sign(
diff --git a/tdrive/backend/node/src/services/documents/services/index.ts b/tdrive/backend/node/src/services/documents/services/index.ts
index 5e82cb85..8c70a5eb 100644
--- a/tdrive/backend/node/src/services/documents/services/index.ts
+++ b/tdrive/backend/node/src/services/documents/services/index.ts
@@ -61,6 +61,7 @@ import config from "config";
 import { MultipartFile } from "@fastify/multipart";
 import { UploadOptions } from "src/services/files/types";
 import { SortType } from "src/core/platform/services/search/api";
+import ApplicationsApiService from "../../applications-api";
 
 export class DocumentsService {
   version: "1";
@@ -976,9 +977,16 @@ export class DocumentsService {
       this.logger.error("invalid execution context");
       return null;
     }
-
-    //TODO: This needs to try in a loop depending on oo-connector response
-    //       when there is already a key
+    if (
+      !editorApplicationId ||
+      !ApplicationsApiService.getDefault().getApplicationConfig(editorApplicationId)
+    ) {
+      logger.error(`Missing or invalid application ID: ${JSON.stringify(editorApplicationId)}`);
+      CrudException.throwMe(
+        new Error("Unknown appId"),
+        new CrudException("Missing or invalid application ID", 400),
+      );
+    }
     let newKey: string;
     try {
       newKey = EditingSessionKeyFormat.generate(
diff --git a/tdrive/backend/node/test/e2e/common/user-api.ts b/tdrive/backend/node/test/e2e/common/user-api.ts
index ec047e68..133a3eff 100644
--- a/tdrive/backend/node/test/e2e/common/user-api.ts
+++ b/tdrive/backend/node/test/e2e/common/user-api.ts
@@ -516,7 +516,7 @@ export default class UserApi {
   async getDocumentByEditingKey(editing_session_key: string) {
     return await this.platform.app.inject({
       method: "GET",
-      url: `${UserApi.DOC_URL}/companies/${this.platform.workspace.company_id}/item/editing_session/${encodeURIComponent(editing_session_key)}`,
+      url: `${UserApi.DOC_URL}/editing_session/${encodeURIComponent(editing_session_key)}`,
       headers: {
         authorization: `Bearer ${this.jwt}`
       }
diff --git a/tdrive/backend/node/test/e2e/documents/editing-session.spec.ts b/tdrive/backend/node/test/e2e/documents/editing-session.spec.ts
index 845ec9c9..fd5d0231 100644
--- a/tdrive/backend/node/test/e2e/documents/editing-session.spec.ts
+++ b/tdrive/backend/node/test/e2e/documents/editing-session.spec.ts
@@ -1,10 +1,13 @@
-import { describe, beforeAll, beforeEach, it, expect, afterAll } from "@jest/globals";
+import { describe, beforeAll, beforeEach, it, expect, afterAll, jest } from "@jest/globals";
 
 import { init, TestPlatform } from "../setup";
 import UserApi from "../common/user-api";
 
 import { DriveFile, TYPE as DriveFileType } from "../../../src/services/documents/entities/drive-file";
 import exp = require("node:constants");
+import ApplicationsApiService from "../../../src/services/applications-api";
+import { afterEach } from "node:test";
+import Application from "../../../src/services/applications/entities/application";
 
 describe("the Drive's documents' editing session kind-of-lock", () => {
   let platform: TestPlatform | null;
@@ -49,6 +52,11 @@ describe("the Drive's documents' editing session kind-of-lock", () => {
       parent_id: currentUserRoot,
       scope: "personal",
     });
+    jest.spyOn(ApplicationsApiService.getDefault(), 'getApplicationConfig').mockImplementation((id) => id === "e2e_testing" ? {} as Application : undefined);
+  });
+
+  afterEach(() => {
+    jest.restoreAllMocks();
   });
 
   it("atomicCompareAndSet allows a single value at a time", async () => {