Hi @Vineeth ,
I did try a few workarounds to delete the Forms tab and restart the outlook , however it was not working.
Did you clear the forms cache in Outlook? (File> Options > Advanced > Custom Forms > Clear Cache)
If that doesn't work, try renaming the FRMCACHE.DAT to FRMCACHE.OLD and check if this helps, when you restart Outlook, and use a form Outlook will automatically reinstall the form.
The location of this file is: C:\Users\User Name\AppData\Local\Microsoft\FORMS
Besides, I would suggest you create a new profile and verify the results.
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