The program 'mate-settings-daemon' received an X Window System error

Hello. I am having issues with mate-settings-daemon not being able to start under a Mint+Mate install.

It was generally working on startup. One thing that was wierd was that it would not start properly if an external monitor was connected at startup, I had to start the laptop, let it boot fully into the desktop, and THEN connect the external monitor.

Well, I brought my laptop on a trip with me. When I started it up without the external monitor attached, it would boot up but then the screen would turn black as it tried to display on the external monitor which was no longer there.

I'm not sure how, but I got it to show the desktop again, but there were no window decorations or background. Eventually after several reboots including attempts to boot old kernel images, I got a desktop and window-decorations back, but it seems I have done something to mate-settings-daemon.

For a while I was getting "Failed to aquire org.mate.SettingsDeamon", but now it doesn't even get that far. It says now:

The program 'mate-settings-daemon' received an X Window System error.
This probably reflects a bug in the program.
The error was 'BadMatch (invalid parameter attributes)'.
(Details: serial 190 error_code 8 request_code 140 minor_code 30)
(Note to programmers: normally, X errors are reported asynchronously;
that is, you will receive the error a while after causing it.
To debug your program, run it with the --sync command line
option to change this behavior. You can then get a meaningful
backtrace from your debugger if you break on the gdk_x_error() function.)

I don't know how to debug or fix this, but a dist-upgrade is not an option on this machine. Please help! I need mate-settings-daemon back! How can I troubleshoot or attempt to repair this issue without a full reinstall or dist-upgrade?