I have answered your other topic, it is best to stay in your own one, yes monitor other topics and see what is suggested but there is no need to also jump in.
@ janharnish
First since your using Vista Home Premium, we will naturally assume that you are using avast Home and not the server version of avast (which forum you have posted).
Download the latest version of avast
http://www.avast.com/eng/download-avast-home.html and save it to your HDD, somewhere you can find it again. Use that when you reinstall. Ensure that you scroll down and select the avast direct download link for the English version and not Cnet as that is for an on-line installation (not what you want to do). - Direct download for avast Home, English version,
http://files.avast.com/iavs4pro/setupeng.exe.
Download the avast! Uninstall Utility,
find it here and save it to your HDD.
- 1. Now uninstall (using add remove programs, if you can't do that start from the next step), reboot.
- 2. run the avast! Uninstall Utility, reboot. If step 1 failed it may be necessary to run this from safe mode, once complete reboot into normal mode.
- 3. install the latest version, reboot.