Again I thank you for your responses.

All the solutions I thought were fixing the problem have eventually failed. I must have some bad MoJo in this form .

I have solved the bleed through issue, so far as of this writing, by adding to my sub-classed edit box functionality, to turn on scroll bars when it has focus and off when focus is lost. This seems to work fine.

Can anyone think of why this approach would be wrong or limit something else?

Thanks again for all your support,

Gary De Lecce