>Thanks for the reply.
>
>That's more or less what we had guessed...But SHOULD we be overwriting things like the MS Common Controls? The only reason for the problem that I can think of without going to look at the install system, is that the versions of the common controls we are distributing are older than the ones on the target machine, which are therefore NOT overwritten, but the newer ones are incompatible. Any suggestions?
>

Not that you're going to like particularly. The alternatives are to either upgrade your app to the latest version of the control, and revise your install to put it in place, or to if the current version of the control is backwards-compatible, instantiate it programmatically from the VersionIndependentProgID (this may not be an attractive alternative for you if you want to drag and drop design your forms, but it would allow the use of whatever the latest control instlaled on the system is.)