yeah the same thing I told here already month ago but well not even an answer.
However, matchprop seems to work as (short)command AFTER you clicked once the shortcut of it and properties seems also to work AFTER you have chosen it once in context menu (right click menu) - there are some more commands that are this way working (like align: it's working with original command but not with shortcommand) or NEVER working like for a rectangle - but it seems also that not many people have these problems otherwise some more would have said something here.
Anyway there is a service pack 1 avaiable for ACAD Mech but don't think this problem gets fixed with it ^.^
so far, André
p.s.: these rituals have to be done every time you start the program new after it was closed - great, uh?
I'm thinking some 2010 files were corrupted when I uninstalled AM & Inventor 2009. So I did a clean uninstall, including removing all Autodesk registry entries, and then reinstalled AM 2010. Works fine now, so problem solved.
I had the same problem and it was working fine this morning, after lunch I had noticed the problem. I have figured out the problem, use the command "DEMANDLOAD" then put the number to 3. I dont know why it's 3 but it fixed the "matchprop unknown command. press F1" and the "properties unknown command" error messages I was getting.