Hi @Nadia ZB
Welcome to Q&A forum ~
Could you please check the Office update channel and Office version number?
- To get this information, please click: File > Account > Product Information.
- Have you done some changes on Office apps? Such as change the Office update channel. Based on my tests, if you want to use Groupby function, please use Current Channel. For more, please refer to: New aggregation functions: GROUPBY and PIVOTBY
If you have already set up a Current Channel for your Microsoft 365 Apps, please run Excel in safe mode. Safe mode can help us troubleshoot the influencing factors of COM add-ins.
- Please press and hold on Ctrl key, click or double-click Excel icon, until Excel asks if you want to start it in safe mode, then please release Ctrl key and click "Yes".
- Then check the Groupby function.
- If Groupby function is back 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 this issue still exists in safe mode, it's recommended to perform an Online Repair for your Office.
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