Office Compatibility Issues

How to Fix Microsoft Office Bugs and Error 1200 on Windows 11

Bushra Parveen Oct 13, 2026 870 views

Question details

Users are experiencing recurring bugs in Microsoft Word, Excel, and PowerPoint on Windows 11, such as broken selections, incomplete fills, and Error 1200 after software updates.

How to Fix Buggy Microsoft Office Apps and Error 1200 on Windows 11

Product: Microsoft Office (Word, Excel, PowerPoint)
Device & OS: Windows 11
Scenario: Using Microsoft Office applications for document editing or attempting to sign in after a recent Windows or Office update.
Observed behavior: Applications behave erratically, presenting issues like incomplete fill operations in Excel, broken text selection anchors in Word, and an Error 1200 message that prevents users from accessing their Microsoft 365 accounts.

Before you start

Ensure your Windows 11 operating system is fully updated, and note down the exact Office app version and error message before troubleshooting to help identify specific issues.

Solution 1Recommended

Resolve Error 1200 by Clearing Microsoft Credentials

Removing corrupted Windows cached credentials can resolve sign-in loops and Error 1200 in Microsoft 365 applications.

Error 1200 typically occurs when the cached login tokens for your Microsoft account become out of sync or corrupted after a system update. Clearing these credentials forces the app to establish a fresh, secure connection.

Disconnect the work or school account

Open Windows Settings by pressing Windows + I. Navigate to 'Accounts' > 'Access work or school'. Find the problematic Microsoft account, click on it, and select 'Disconnect'.

Remove cached credentials

Click the Windows Start button, type 'Credential Manager', and press Enter. Select 'Windows Credentials' and scroll down to the 'Generic Credentials' section.

Delete Office credentials

Locate any entries starting with 'MicrosoftOffice'. Click the drop-down arrow next to each one and select 'Remove'. Repeat this for all Office-related credentials.

Restart and sign in

Restart your Windows 11 device. Open Word or Excel and sign in again with your Microsoft account credentials when prompted.

Resolve Error 1200 by Clearing Microsoft Credentials

Credential Reset Complete: After deleting these credentials, Microsoft Office will prompt you to log in cleanly, which usually clears the Error 1200 blockage entirely.

Solution 2

Repair or Reinstall Microsoft 365 Apps

If Excel fills or Word selections are broken, running the Office Online Repair tool or reinstalling the suite can fix corrupted application files.

Free Microsoft Office alternative

Switch to WPS Office for a Bug-Free Experience on Windows 11

If Microsoft Office applications continue to throw errors or experience glitches like Error 1200 and broken tools on Windows 11, try WPS Office. It is a highly stable, lightweight alternative that offers a familiar interface and seamless document editing without the heavy system footprint and constant update bugs.

1. Download the software: Visit the official WPS Office website and download the free installer for Windows.
2. Install and set up: Run the installer. During setup, you can optionally set WPS Office as your default application for Word, Excel, and PowerPoint files.
3. Open your files: Double-click your existing Microsoft Office documents. They will open directly in WPS Office with all original formatting preserved.

100% compatible with Microsoft Office formats (DOCX, XLSX, PPTX)Free and lightweight, avoiding heavy update errors and credential loopsFamiliar ribbon interface for a zero learning curveHighly stable performance natively optimized for both Windows 11 and Windows 10

microsoft office alternative - wps office

Frequently Asked Questions

Why do I get Error 1200 when opening Word or Excel on Windows 11?

Error 1200 typically occurs due to corrupted or outdated cached login credentials following a system or software update. Clearing your saved Microsoft credentials in the Windows Credential Manager and reconnecting your account will usually resolve this sign-in issue.

Are Microsoft Office bugs exclusive to Windows 11?

No. Official investigations show there is no confirmed general Office defect unique to Windows 11. Many reported issues, such as incomplete Excel fills and Word selection glitches, can also occur in Office on Windows 10 and are generally related to application-level corruption rather than the operating system itself.

How can I fix text selection losing its anchor in Word?

This UI glitch is often caused by a corrupted installation file or an incomplete background update. Running an 'Online Repair' for Microsoft 365 via the Windows Settings > Installed Apps menu is the most effective way to restore normal text selection behavior.

Office App Problems