Error Codes

Match Office error codes to practical fixes—install, activation, update, and runtime failures explained briefly.

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1267 Resources

How to Fix Microsoft 365 Error 500121 on a New Phone

◷ 2026-09-29

Learn how to resolve Microsoft 365 Error 500121 when signing into a work account on a new phone. Troubleshoot MFA authentication failures with these solutions.

How to Fix Error 399287 When Sending a Phone Verification Code in Outlook

◷ 2026-09-29

Learn how to resolve Error 399287 during two-step verification in Outlook. Discover steps to reset authentication methods or contact Microsoft Support.

How to Fix File Explorer Preview Pane Blocking Files in Windows

◷ 2026-09-29

Learn why the Windows File Explorer Preview Pane blocks certain downloaded files for security reasons, and discover how to unblock and view your documents safely.

How to Fix Outlook Calendar JSON Parsing Error When Publishing an Iframe

◷ 2026-09-29

Learn how to troubleshoot and fix the Outlook error 'GetAnonymousCalendarSessionData failed: Unexpected end of JSON input' when embedding a calendar on a website.

Fix Microsoft Entra ID 500-Object Directory Quota Error (AADSTS90093)

◷ 2026-09-29

Learn how to resolve the Microsoft Entra ID 500-object directory quota limit and AADSTS90093 error by verifying tenant configuration and contacting support.

How to Fix Windows Activation Error 0xC004F074 and Access Free Office Options

◷ 2026-09-29

Resolve Windows activation error 0xC004F074 caused by KMS volume licensing issues, and discover ways to use Microsoft Office applications for free.

Fix SharePoint 2019 Potentially Malicious XOML Node Error

◷ 2026-09-29

Learn how to resolve the potentially malicious XOML node error in SharePoint 2019 workflows caused by strict security validation after recent updates.

How to Fix Internal Error (System.NullReferenceException) When Opening Excel 3D Maps

◷ 2026-09-29

Learn how to fix the System.NullReferenceException internal error when opening Excel 3D Maps. Troubleshoot add-in conflicts, use Safe Mode, or repair Office.

How to Fix Outlook Cannot Open OST File and Must Connect to Exchange

◷ 2026-09-29

Learn how to resolve the Outlook error stating it cannot open the OST file and must connect to Microsoft Exchange. Discover easy steps to recreate or repair your data file.

How to Fix Excel 365 Not Supporting External SQL Subqueries

◷ 2026-09-29

Learn why Excel 365 version 2511 fails to support external SQL subqueries and discover practical alternatives like Power Query and data consolidation.

How to Fix SharePoint Online REST API 429 Throttling Errors

◷ 2026-09-29

Learn how to resolve SharePoint Online REST API 429 Too Many Requests throttling errors using exponential backoff, Retry-After headers, and request batching.

How to Fix WMIC QFE No Instances Available Error in Windows

◷ 2026-09-29

Learn how to fix the WMIC QFE "No Instances Available" error in Windows by repairing the WMI repository, using PowerShell alternatives, or running DISM.

How to Fix Windows 'Service Did Not Respond in a Timely Fashion' Error

◷ 2026-09-29

Learn how to fix the 'Service did not respond in a timely fashion' error in Windows by extending the service timeout limit and running system file checks.

How to Fix Microsoft Error Code 3399811147 and Error 7ita9

◷ 2026-09-29

Learn how to troubleshoot Microsoft error code 3399811147 and error 7ita9 by re-registering the AAD Broker Plugin and clearing corrupted identity credentials.

How to Fix Word Selection Locked and Product Activation Failed Errors

◷ 2026-09-29

Learn how to resolve the 'selection is locked' and 'Product activation failed' errors in Microsoft Word by checking document protection and renewing your license.

How to Fix Outlook Hyperlinks Blocked by Computer Restrictions

◷ 2026-09-29

Learn how to fix the Outlook error where hyperlinks are blocked due to computer restrictions. Discover solutions to reset your default browser and repair registry settings.