Every time the avast screen saver cuts in, during the <initializing stage> (or immediately after) the screen saver cuts out and a microsoft error reporting window pops up.
the information below is taken from the error report, I can post the whole technical log file if needed but very large. This happens every time even if I preview the screensaver.
AppName: avastss.scr AppVer: 4.7.936.0 ModName: msvcr71.dll
ModVer: 7.10.3052.4 Offset: 0000fedc
<edit> ps a repair form add/remove programs did not help