In Word, there is a big difference between the language of specific text ranges (words or even single characters) and the default proofing language.

If "Detect language automatically" is selected in the Language dialog box (Review > Language > Set Proofing Language), you should turn it off. That setting makes Word guess the language at the insertion point as you type, and the guesses are often unsuccessful.

If you select all the text in the document and (re-)apply English and also clear the check box next to "Do not check spelling or grammar," then are you able to check the spelling again?

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Stefan Blom
Microsoft Word MVP

Microsoft 365 apps for business
Windows 11 Professional

I know you have some ideas on how to correct the Spell Check but I thought I would just start all over. I have not made any changes to Word 2016 settings for years. I removed 2016 Word for Widows 10, 64 bit off my laptop. I see all the word documents are on my laptop but they are not valid.

Could you give me the steps to reinstall 2016 Word. We cannot do anything until 2016 Word is installed. Hopefully that will resolve my issue.

I tried to find the steps on the internet but nothing made any since including Microsoft downloads.

Reinstalling will do nothing for this AFAIK.

Did you follow the steps I gave?

1. Select a word that is obviously misspelled but not flagged as an error.
2. Check the language setting under the Review tab.
3. Does it have "Do not check..." checked?
4. If so, in the document use Ctrl+A to select all text.
5. Check the language setting under the Review tab again.
6. Make sure that checkbox is clear.

Spelling Checker Does Not Work! - Proofing Language Keeps Changing - Solutions

If you really want to reinstall (which will not help):

• Uninstall Office from a PC - Office Support
• Download and install or reinstall Office 2016 on a PC - Microsoft Office

Installing Word is simply a matter of running the installation program and entering the license key when prompted. What part of the installation process is giving you trouble?

As mentioned I have not made any changes to Word 2016 in years. So the advice given to resolve Spell Check was not relevant. I was able to reinstall Word 2016 after I found the steps on internet sites. Most internet sites recommended that if you have not made any changes to do a reinstall. Most often a reinstall will fix issues. The reinstall fixed my Word 2016 Spell Check problem.