No AutoCorrect spell check in Outlook 2021 client

1. Check the spell checking settings: Open Outlook, click File > Options > Mail.
In the Compose Messages section, click Spell Check and AutoCorrect.
Make sure that the “Check spelling as you type” and “AutoCorrect” options are enabled.
2. To reset the spell check dictionary: Close Outlook.
Press Win + R, type %appdata%\Microsoft\UProof, and enter.
Delete the Default.acl and Custom.dic files.
Restart Outlook and check if the spell check function is back to normal.
3. Fix Office: Open Control Panel > Programs and Features.
Locate Microsoft Office, right-click and select Change > Repair.
Wait for the repair to complete and restart your computer.
4. Update Outlook: Open Outlook, click “File” > “Accounts” > “Update Options” > “Update Now “Make sure Outlook is updated to the latest version.
5. Disable Add-Ins: Open Outlook, click “File” > “Options” > “Add-Ins”.
Select “COM Add-ons” in the “Manage” drop-down menu and click “Go”.
Disable all add-ons, restart Outlook and check if the issue is resolved.
6. Check the language setting: Open Outlook and click File > Options > Language.
Ensure that the spell check language is set correctly. If necessary, click “Add another editing language” to install the required language pack.
7. Use Clean Start: Press Win + R, type msconfig, and enter.
In the “Services” tab, check “Hide all Microsoft services” and click “Disable all”.
In the “Startup” tab, click “Open Task Manager” and disable all startup items.
Restart your computer and check if the problem is solved.