I haven't any experience of this but even though you have the latest version of XP Home, etc. since it is relating to the Microsoft Visual C++ Runtime Library, is it possible that there is an update for that ?
I have heard of other Microsoft Visual C++ Runtime errors relating other programs, namely Outpost Pro firewall and the suggestions on that forum was to update the Microsoft Visual C++ Runtime Library.
Other than that I haven't much to offer, but looking at the Program: oath, where are you running the setupeng.exe from and what folder are you trying to install it in ?
The avast.setup is used for the program and VPS updates, so in theory the program must have been installed, probably rebooted and this is happening because a connection is present shortly after boot and the avast auto update is trying to check for updates.
So can you be a little more detailed as to when exactly this error happens. I'm just calling it a night so I hope this information may help others trying to help.