Microsoft 365 Error Codes

Fix Microsoft Office Authentication Errors on RDS and Horizon Servers

Maira Mehtab Sep 21, 2026 868 views

Question details

Users need to resolve recurring Microsoft Office authentication loops displaying error codes such as 1001, 7ita9, and 80070002.

Product: Microsoft Office 365
Device & OS: Remote Desktop Services (RDS) and VMware Horizon
Scenario: Launching Microsoft Office applications via virtual desktop infrastructure (VDI) environments on segmented networks.
Observed behavior: Office applications get stuck in a continuous authentication loop, repeatedly prompting for credentials and throwing errors like 1001, 7ita9, or 80070002 despite clearing cache folders.

Before you start

Before proceeding, ensure you have administrative access to the network firewall configurations and the RDS or VMware Horizon servers.

Solution 1Recommended

Disconnect Work or School Accounts and Re-authenticate

Refreshing the Windows account connection can resolve corrupted token states that trigger the continuous authentication loop.

In VDI environments, cached credentials can become desynchronized from Microsoft Entra ID. Disconnecting and recreating the profile connection forces Office to request a fresh authentication token.

Access Windows Settings

Navigate to the Windows Start menu, open 'Settings', and click on 'Accounts'.

Disconnect the Account

Select 'Access work or school', locate the connected Microsoft account, and click 'Disconnect'.

Sign Out of Office

Sign out of all active Microsoft Office applications (Word, Excel, etc.) and close them completely.

Test with a New Profile

Create or log into a new Windows user profile and launch Office to test if the authentication succeeds.

Solution 2

Verify Firewall Access to Microsoft Endpoints

Blocked authentication URLs on segmented networks can prevent Office from communicating with Microsoft servers, causing sign-in failures.

Solution 3

Troubleshoot FSLogix Profiles and Entra ID

Misconfigured roaming profiles or missing Entra ID bindings can break single sign-on capabilities across remote sessions.

Free Microsoft Office alternative

Use WPS Office for a Hassle-Free Remote Desktop Experience

If persistent Microsoft Office authentication loops and FSLogix profile issues are disrupting your workflow on RDS or Horizon servers, consider switching to WPS Office. It provides a lightweight, highly compatible alternative that bypasses complex cloud authentication requirements, ensuring seamless document editing for all remote users.

1. Download the Installer: Visit the official WPS Office website and download the installation package to your host server.
2. Deploy to VDI Environment: Install WPS Office on your remote desktop golden image or provision it across your RDS environment.
3. Open Documents Instantly: Launch WPS Office and open your existing Microsoft Office files locally without dealing with authentication barriers.

Operates independently of complex Microsoft Entra ID and mandatory cloud authentication loops.Fully compatible with Microsoft Word, Excel, and PowerPoint file formats (.docx, .xlsx, .pptx).Lightweight architecture makes it highly optimized for RDS, VMware Horizon, and VDI environments.Free to use with a familiar, easy-to-navigate interface for quick user adoption.

microsoft office alternative - wps office

Frequently Asked Questions

Why do I keep getting Office error 1001 on my remote desktop?

Error 1001 typically occurs in VDI environments when local cached credentials in the IdentityCache or OneAuth folders become corrupted or fail to synchronize properly with the Microsoft Entra ID session.

Will clearing the IdentityCache folder permanently fix the authentication loop?

Clearing the IdentityCache and OneAuth folders often acts as a temporary fix. For a permanent solution, you must ensure that your network firewall allows traffic to all required Microsoft endpoints and that your FSLogix profiles are correctly configured.

How do I test if my firewall is blocking Microsoft authentication URLs?

You can open a web browser on the affected RDS or Horizon server and attempt to navigate to endpoints like login.microsoftonline.com and aadcdn.msauth.net. If the pages fail to load, your firewall or proxy is likely blocking the necessary authentication traffic.

Microsoft Office Error Codes