Microsoft 365 Error Codes

How to Fix Microsoft Office Error Tag 58tm1 in Word or Excel

Amos Gikunda Sep 27, 2026 870 views

Question details

Users need to resolve Error Tag 58tm1 that prevents them from opening documents in Microsoft 365 applications.

How to Fix Microsoft Office Error Tag 58tm1 in Word or Excel

Product: Microsoft Word, Microsoft Excel (Microsoft 365)
Device & OS: Windows Server, Remote Desktop Services (RDS)
Scenario: Attempting to open Word or Excel files while logged into a Microsoft 365 account on a Windows Server or Remote Desktop Services farm.
Observed behavior: An error message displaying Tag 58tm1 appears, blocking access to the file and indicating a failure in the Microsoft 365 account authentication process.

Before you start

Before modifying your system registry, ensure you have saved all open documents, fully closed all Microsoft Office applications, and backed up your current registry state.

Solution 1Recommended

Clear Office Identity Registry Keys

Removing corrupted identity entries from the Windows Registry is the most effective way to resolve authentication loops in Remote Desktop environments.

This method forces Microsoft 365 to rebuild your login credentials from scratch. It requires administrator access to the Windows Registry and is highly recommended for Windows Server 2022 and RDS users.

Open Registry Editor

Press the Windows key + R to open the Run dialog, type 'regedit', and press Enter to launch the Registry Editor.

Navigate to the Identities folder

Go to the following path: HKEY_CURRENT_USER\Software\Microsoft\Office\16.0\Common\Identity\Identities.

Delete affected identity entries

Right-click and delete the identity folders located under the Identities key to clear the cached credentials.

Log off and sign back in

Log off from Windows or your Remote Desktop session completely, then sign back in.

Complete MFA

Open Word or Excel, sign in to your Microsoft 365 account, complete the Multi-Factor Authentication (MFA) prompt, and reopen your file.

Registry Warning: Only delete the folders strictly inside the 'Identities' path. Modifying other registry keys may cause system instability.

Solution 2

Disconnect and Reconnect Your Microsoft 365 Account

Manually signing out and back into the Office desktop application can quickly fix minor session glitches.

Solution 3

Re-authenticate via the Microsoft 365 Web Portal

Opening the file from the web version of Office first can help bypass desktop authentication blocks.

Free Microsoft Office alternative

Use WPS Office to Avoid Complex Authentication Errors

Tired of dealing with server-level Microsoft 365 login errors like Tag 58tm1? WPS Office provides a robust, lightweight alternative that works seamlessly offline. You can edit your documents without being forced through complex network authentication loops.

1. Download WPS Office: Visit the official WPS website and download the free installation package for your Windows PC or Server.
2. Install the application: Run the installer and follow the on-screen prompts to complete the setup in minutes.
3. Open your files directly: Double-click your existing .docx or .xlsx files to open and edit them immediately, completely bypassing Microsoft 365 login errors.

Free and lightweight complete Office suiteFully compatible with Microsoft Word (.docx) and Excel (.xlsx) formatsNo complex registry edits or server authentications required to edit local filesFamiliar user interface for a seamless transition

microsoft office alternative - wps office

Frequently Asked Questions

What causes Microsoft Office Error Tag 58tm1?

This error is typically caused by a corrupted authentication token or session glitch in Microsoft 365, frequently occurring in Windows Server 2022 or Remote Desktop Services (RDS) environments where user profiles and identities are strictly managed.

Do I need administrator privileges to fix Error Tag 58tm1?

If simply signing out and back in does not resolve the issue, you will need administrator privileges to access the Windows Registry Editor and delete the corrupted identity keys.

Can I edit my Word and Excel files if Microsoft 365 remains locked out?

Yes. If you cannot bypass the authentication error, you can use a compatible free alternative like WPS Office to open, edit, and save your .docx and .xlsx files locally without needing a Microsoft account login.

Microsoft Office Error Codes