an update - I sent the Unblock suggestion to my QA, who used
it, and was able to get into the help file. But when she copied the
.chm to the development environment to be included in the build,
our developers can't open it, and there is no Unblock available.
For now, because we are doing an interim build, we will just
incorporate the file as is into the build and see how the help
system works from within the program, which is how our clients
access it. We have never had a complaint from clients, by the way,
about accessing topics. It just seems like in the past two or three
months, something has changed on PCs here in the office to cause
these errors when the chm is viewed as a standalone. And not on
every PC - I have never had the problem, either on my own
production laptop or on my home PC. It's enough to drive me to
drink. Heavily.