InstallShield Express stopped working

2007-08-22 06:58:01 PM
IS Express (that came with BCB5) has stopped working on XP-Pro PC's with the
latest OS updates. Having worked flawlessly for years and years, any update
installed using IS now, instead of updating myapp.exe, leaves the latter
intact and creates a new file myapp.1 (.2, etc etc). These are the .exe
files that should have updated the original. Some observations...
-Still works fine if PC started in Safe Mode
-Firewall disabled
-No a/v BUT if I install a/v then the updates work properly, even if I then
disable or uninstall the a/v. (Note - a/v not required since PC's operate
in closed, secure network not connected to Internet).
I have ensured that IS is set to update always (as it has always been).
Changing IS version is not an option.