Hello Peter,
That's an interesting one, not seen that one before. The only tricky problem is that I don't have a machine running W7 64bit .... at the moment. Going to see if work IT can knock me up said machine so I can debug the issue. Had a look on-line and there seem to be lots of people getting a message like this and lots of misinformation flying around as to the reason. I will look into it, if I can replicate the problem I can fix it.
Small favour :
If anyone else is running W7 64bit with any client program and fancies having a go at a large move say 2000 steps I would appreciate the feedback just to see if it's a universal problem or just particular to Peter's setup.
I'll get onto it
Clear skies,
Dave