https://help.tallysolutions.com/docs/te9rel60/Licensing/Uninstalling_Tally.ERP_9.htm

Uninstalling Your Tally.ERP 9

You can uninstall Tally.ERP 9 to discontinue using the application. Uninstallation may also be required when an error occurs, and you need to reinstall.

To uninstall Tally.ERP 9

1.    Go to Tally.ERP 9 installation folder in your computer.

2.    Double-click the Setup.exe icon.

3.    Click Uninstall.