Well, I uninstalled MC 22 and in the process discovered that MC 21 was still installed; at least it was showing as being installed in the Windows Apps list.
When you install an update, from 21 to 22 for example, shouldn't the installed be smart enough to uninstall the previous version? Or at least tell you that you have to uninstall it manually? I can't think of any other program that I've dealt with in the last decade which doesn't have this basic functionality built in. Nor did any of the upgrade instructions on the JRiver website mention that I had to uninstall the old program first, or backup my settings. Nor did the email I got when I bought the upgrade.
So now I have MC22 reinstalled, but the program guide problem that I was dreading has returned. I've spent the last 2 hours trying to get my channel listings and TV tuner and program guide to match-up and work but it doesn't. Every time I think I have it right the MC2XML program pops up and insists on rescanning everything, and invariably messes it all up again. I try to cancel it by closing the dialog boxes but it keeps coming back.
Many of my channels are now blank, showing no programs, but I don't know how to update the listings without a complete channel rescan, which as I said above, messes up most of my channels.