accelerator gone crazy, and so have I

:foolish Me, the new fool, again. In addition to my problems with Avira antivirus, my accelerator program started causing all kinds of problems. I uninstalled it, reinstalled it, and got a message during set up saying I had to reboot the computer to do some task and finish set-up. So I rebooted, and got that same message as before, as tho I hadn't just rebooted. I went thru the whole process 3 more times with the exact same results. Finally, I uninstalled the accelerator. What is going on with my system. I am always so careful, and my scans showed everything clean. Am I infected?
Sheena