On what computer(come on folks, how is anyone to help when you give no details of your setup)
Given that I am a Windows user, to uninstall PT, go to Control Panel(Category view) and select Uninstall a Program. Once the list is populated, find Pro Tools and right-click on it. Select Change. In the next window, check to also remove the HD driver(and prefs), then click Okay. What I have also been doing(with success) here, is find the Pace 64 item and also uninstall that. Then reboot and run the installer(Run as Admin) for the version you want. The first thing it will tell you is something about "Pending install of Pace..." Click Okay and it will start(by reinstalling the PACE driver you removed earlier). In a moment, it will tell you it needs to reboot(tell it Okay). Once it reboots, it should(in a few moments) pop up with the PT installer so you can finish the install(and reboot again).
BTW, if you would, go to your duplicate of this post and select Edit, then scroll down and find the delete button
