Setup.exe do not work

Suddenly Setup.exe in my WinXP do not work. Afterdouble click on Setup.exe (InstallShield Corp)it start to show the timeglass and after a few second it stops with out showing any text message on the screen. When doubleclick again nothing happens and no timeglass is shown.
When clooseing Windows the setup sequence starts but then Windows is closing down. My theory is that another process is blocking the setup.exe to be executed.
Someone knows what to do?