While trying to log in to play chess online, I get the following message: Client is incompatible with the server (ERR: 50) Anyone know how to fix this?

You need to install the appropriate patches.

You'll find them in the Chessmaster 10th Edition Downloads.

where do i find patchs for chessmaster 9000

cuz i got the same problem on 9000

You can find the patches in the FAQ's post. It doesn't say READ THIS FIRST for nothing, you know



P.S.: Online play for Chessmastter 9000 doesn't work anymore, but it doesn't mean you shouldn't install the patch anyway.