Install Parallels Internet Security = zzzzzzzz

I've repeatedly tried to install Parallels Internet Security from the PD menu bar, but nothing happens.

In the VM, I have navigated to the Parallels folder and found avp.exe, but it shows as a 0 bytes file. Double-clicking gets me "....is not a valid Win32 application" error message.

I have been "arguing" with the v4.0 installation for a couple of days now, so it's possible I've turned off a service or something somewhere along the line as I tried various solutions offered here for various problems. Any thoughts on where I should be checking for this issue?

This is the final issue - I'd love to know that I have everything running as designed.