i have uninstalled it many times but not getting success
Did you stop all XAMPP components and make sure any running as a service were also stopped and uninstalled as a service including the Control Panel before uninstalling XAMPP?
Only then it is safe to delete the xampp folder - don't try reinstalling xampp over the top of an already installed xampp or you will have issues.
Make sure apache is stopped and un-tick the Svc
box if ticked then close the Control Panel.
Go to .\xampp\apache
and double click on apache_uninstallservice_2.2.bat
Now open your Control Panel again and try and start Apache but don't tick the Svc
box unless you really want Apache to start every time you boot your PC.