Why does Word keep switching my proofing language?

Word's 'Detect language automatically' feature can misidentify your text language, especially with technical terms or short phrases. Disable it via Review > Language > Set Proofing Language > uncheck 'Detect language automatically.'

Fix: Word Keeps Changing Language or Keyboard Layout

Why Word Changes Your Language

Word can automatically detect and switch languages, but this feature sometimes misidentifies text, causing spell check and formatting issues.

手順

Step 1: Set Your Default Language

Go to File > Options > Language
Under Office authoring languages and proofing
Move your preferred language to the top
Click Set as Default

Step 2: Disable Automatic Language Detection

Select all text: Ctrl+A
Go to Review > Language > Set Proofing Language
Select your language
Uncheck Detect language automatically
Click OK

Step 3: Fix Keyboard Language Switching

Windows may switch your keyboard layout with Alt+Shift or Ctrl+Shift:

Go to Windows Settings > Time & Language > Language
Remove languages you don’t use
Or change the keyboard switching hotkey:
- Go to Advanced keyboard settings > Input language hot keys
- Change or disable the shortcut

Step 4: Fix the Normal Template

If language changes persist:

Close Word
Go to %appdata%\Microsoft\Templates
Delete Normal.dotm
Reopen Word and set the correct language in a new document

For Multilingual Documents

If you intentionally use multiple languages:

Select each language section separately
Set the proofing language for each section individually
Keep “Detect language automatically” enabled only for multilingual content