CTGW won't start after reinstallation

[Ironclad]

I uninstalled the game some time ago. On attempting to reinstall it today - the original setup loads, using the update facility I installed the latest patch. During installation I got two messages telling me a couple of items will have to be installed on reboot (references to the auto-exec and an audio file). When I attempt to reinstall after reboot I get the following three messages in sequence, and the program doesn't start.

prog.dat is encrypted and you have not provided the correct code. Go to the next item.

DynaZIp UNZIP error. User skipped this operation.

Runtime: Failed to extract project file to memory.

[VPaulus]

Check if your Internet security programs (like anti-virus) aren't interfering with the installation of the update.

[Ironclad]

Thanks, spot on, it looks like zone alarm was blocking it.