Error of avast! 4.8 home after System Restore

[Sakurako]

uninstalled avast! 4.8 home and upgraded to avast! Internet Security beta before System Restore
Problem: could not start or uninstall restored avast! 4.8 ~
System Restore via Boot Option [Repair]
Operating System: Windows 7 Enterprise x32 Trial (Build 7600)

[Tarq57]

Why did you use a System restore after uninstalling the AV/installing a new version?
When you use System restore, not all the files on the system are restored, although the registry entries that pointed to those files are.
So you have a registry that thinks Avast 4.8 is installed, but no Avast 4.8 files on the system, because you removed them.

What do you want to achieve? We can talk you through that. A full uninstall/reinstall using the cleaning tool is likely to be one of the steps required.

Are there any other problems with your computer (using system restore suggest there are.)

[Sakurako]

• A previous Windows System Restore reported as not properly restored. However, System Restore via [Repair] could fix the problem
• Downloading uninstaller might fix the problem. However, probably it would not be secure to enable Network Connection without antivirus protection
• As suggestion, probably better if built-in skin file(s) could be combined with the manager to avoid the problem
• Not sure about other software, but currently no error prompt. And Opera has fixed a problem with tab (off-topic?)