I updated the driver for the USB Smooth Stepper and now when I attempt to launch M3 it hangs at the screen splash.  I backed out the driver but I'm still stuck at the start.  Any ideas short of re-installing M3 all over again?

TIA,
Ken

What ver of Windows? Is this the only program that won't launch? Sounds like a corrupt USB driver or a conflict issue. Even uninstalling bad drivers sometimes won't fix the problem. If you created a restore point before updating the driver (which should always be done) you could roll back to a previous date and see if that corrects it.   

Win 7 and I did roll back the driver.  M3 is the only app that will not run.