installed XP Pro 64 bit edition due to it being inexpensive and is only temporary but when i tried to update my nvidia drivers to the latest version the system would hang on reboot so after a week of trial and error on removing auto start up programs traced it to the avast ashdisp which I assume is the systray icon executable? once i stopped this I was able to install the current nvidia drivers + seems it was interfering with other programs that installed a systray icon + no need to tell me of a solution this is only for those who will have this happen to them
Your assumption is correct.
Strange that nvidia drivers have anything related to the avast system tray icon… very strange… It shouldn’t have being connected each other…
thanks a bunch me not alone still using avast 4.7 but just have to execute it using ashavast.exe so again thinks this is not the fault of the program but with XP Pro 64bit version mostly being used as a server and not stand alone OS and Microsoft says sorry charlie you stupid enough to use this for home use 
found out that there is a bug with 32 bit software that attempts to place their icons in the systray the + still have the rest of the installable avast software running at start up lastly thanks again for allowing us poor folk to use this software for free :
+ forgot to state for those running XP Pro 64 to run msconfig click startup and then disable the ashdisp startup item only no need to uninstall avast 4.7