PHD not guiding

[chrisseal42]

HI 

I have PHD on my laptop and until recent it will not guide. I balanced the scope again and then all seemed ok and guided ok. But tonight it refuses to guide and am now on the oblject. I have re calibrated twice on Vega and once on a fainter star near NGC 6888. The fact that it work only three weeks ago makes me wonder if its the laptop. 

[Freddie]

Will need a few more details to be able to help.

[davedownsouth]

Does it do a calibration and then fail to guide, or does it not even calibrate?  I assume you have checked that the computer is communicating with the mount Ok?

NB.  Yes, some info on your set-up would be useful