... where can I find support for this issue? I have not been able to get "on demand scan" to work for some time now (Error, "C:\Program Files|McAfee|VirusScan Enterprise|scan32.exe /edit), among other issues (google re-directs)...
You should check that the file scan32 is at the location shown.
If not, something happened to corrupt or modify your installation of VirusScan.
If it is, then the executable itself may be corrupted.
Try invoking the command yourself, manually. It should open the window that you are familiar with for running OnDemand Scan.