Do you mean the dynamic array functions, like Sort, Filter, Unique functions do not work on your Excel 2021?
If so, is there any error message? These dynamic array functions are supported on Excel 2021.
I suggest you go to Excel, click File > Account, check the version number under "Product Information".
You may click Update Options > Update Now, update Office to the latest.
You may test these functions in Safe Mode. Please press and hold on Ctrl key, click or double-click Excel icon, until it asks if you want to start it in safe mode, then please release Ctrl key and click "Yes".
- If these functions work in Safe Mode, please click File > Options > Add-ins > Manage COM Add-ins, click Go. Clear the check boxes for any enabled COM add-ins, select OK.
- If not, it's recommended to perform an Online Repair from Control Panel.
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