dog,

It is not necessarily the fault of Avast. What version are you trying to install…Home or Pro?

Avast can be touchy during installation if there are any other Windows programs running in the background. It sounds like you have a bad install, or maybe a corrupted file/s.

Have you attempted to reinstall? If not, before doing so, download a copy of Avclear (for Avast 32) or Avclear4 (for Avast 4) from http://www.avast.com/i_idt_1336.html which will completely uninstall the copy of Avast. The Windows Add/Remove does not always remove everything.
Try whichever program you need, shut down all Windows programs except System Tray and Explorer (if your system has it), and try a reinstall.

Let me know how it goes.

Remember…Things happen!

:slight_smile: