>>Maybe NT just doesn't Like you Bruce. :-) Probably something to do with your employer. :-) Jim's code seems to work pretty well for me here, and we only have NT machines.
>
>You have no ghost at all in NT on grid columns with that code? It's quite noticeable if you have it, it's sort of like an ugly, partial mouse trail. I only have the one NT machine to test on, it could be guilty of a problem, I guess. I have exactly the same trouble with George's API code that he posted...
>
>It *appears* to have the correct mouse driver, maybe I should experiment, though...

Yep, created a test form, drug a table to it, put the code in the grid's mousemove, headers' mousemove and text1 mousemoves, ran it and it looks fine to me. Removed the code from the header mousemove, ran it and ok arrows over the grid controls but standard header arrows over the headers.

You should really find out what this ax NT has to grind with you is specifically. :-)