You say "install some programs" and "new update".
Are you installing programs or updating existing programs.
not a valid Win32 application is a microsoft thing,maybe the file is corrupt,damaged or whatever.
Delete the files and if you like run a reg cleaner such as CCLEANER then try again.
Are you downloading from a reputable site?
I am having problems when trying to install some programs like Ad-Aware and ZoneAlarm (new update). When trying to install, it send me a message telling: "(aaw2007 or zonealarm) is not a valid Win32 application". I have an AMD Semprom 3500 with XP Home. What that means and what should I do?. Thanks, Walt