I just installed MM7 on a Windows 7 64 bit machine. I'm encountering a really wacky glitch where my party is constantly strafing to the right. I don't have any gamepads plugged in, and I even unplugged my keyboard during the game to see if made a difference, and it didn't.

I checked the MM7.ini file and alwaysStrafe is set to zero. I applied v1.6.1 of Greyface's patch and it made no difference.

Any ideas what might be causing this?

You need to install the latest unofficial patch from GreyFace:
http://sites.google.com/site/sergroj/mm

It's caused by a floating point rounding error in the original code that only manifests itself on certain systems. GreyFace only recently solved it, but it's been a lifesaver for me as well.

Enjoy!

If the latest version is 1.6.1, I've already tried that with no luck.

On a whim, I changed the processor affinity to use just one core instead of four, but that didn't help either.

Hmmm... well, that is a headscratcher, then. Sorry I missed your original comment about installing GrayFace's patch.

The issue greyface fixed isn't exactly strafing; it's moving faster in some compass directions. This has been a long standing issue (for a decade) and greyface's latest patch is the only fix.

What you're describing sounds more like a controller issue? Do you use both a usb keyboard and usb mouse, sometimes they can conflict especially if they have their own 3rd party drivers.

Do you always deviate to the side while moving no matter what direction you're facing? If you do then it isn't the rounding error thing greyface fixed.