Please remove current traces of AVG using this utility:
Afterwards you can download 8.5 installation file here:
However, I would suggest to try to install AVG 9 once again after using remover tool.
Tried to take advantage of the upgrade to 9 but everything went badly afterwards. Both IE and Firefox wouldn't work. Used sytem restore to get back to a previous stable environment but now AVG will not work at all. When I tried the unistall it came up with a dialog box message "Installation failed" Any ideas as to how I can remove all traces of Avg 8.5 and 9 and do a fresh reinstall of 8.5. I think I have seen enough of AVG 9