Thank-you but yes I deleted the old Qlik folder after uninstalling 2,2 (using the setup program, not the control panel), I did not find in Qlik processes running in the task manager but I restarted the PC just to be safe anyway, and I ran the program as admin from its actual location and not the shortcut icon. I also tried running repair a few times and there are no blank spaces in my account. Nothing changes, I still only get a blank screen after the splash screen.
One thing, I am using Windows 10. Could this problem be related to that?