I had this exact error message appear on the Fire tablet, trying to connect (for the first time) to a Windows 7 64-bit laptop (I installed the Windows 8.1 software).
On the laptop, the error message said “MCT Driver detected – incompatible display driver”. Supposedly there is a “Spacedesk Driver Console” that will allow you to find and remove any incompatible drivers, but I could not find that software anywhere. The only program that installed on my laptop was the basic “Spacedesk Server” software.
So, I gave up and uninstalled Spacedeck from the laptop. But then I saw in the list of programs to uninstall, something called “Trigger External Graphics Family” from MCT Corp. That was the name from the error message. I uninstalled that Trigger software, reinstalled Spacedeck, and it works fine.
I found online discussion of possible problems with uninstalling Trigger External Graphics Family, but solutions were available and in any case those problems (trouble with Microsoft Word and Excel) did not happen on my laptop. “Trigger” was apparently auto-installed at some point for another external monitor or projector, no longer needed I guess.