>We have an install routine that calls a MESSAGEBOX() routine (VFP5). We found that NT hangs after that call. We have made it happen in three different places in the program.
>
>Note: This is a VFP EXE that is called after installing programs using the VFP Setup.exe (distributed application). (Yes, I know there are better install programs)...
>
>Anybody else seen this?
>

Nope, but I'd venture a guess that the machine either has never had NT SP3 or later applied, or has inconsistent components in place - most likely someone applied an NT Service Pack, later had to go back and load stuff from the initial distribution disk and failed to reapply the NT Service Pack.

I'd recommend reapplying the latest NT Service Pack previously applied to the system if its at SP3 or later (at least SP3; SP5 is available now for download from MS's web site, and SP6 should be out in the not too distant future.) The internal implementation of MESSAGEBOX() for VFP calls a basic Win32 service, so there's an indication that things other than VFP may be affected.

I'd also make certain that you have the latest Setup Wizard patches for VFP5, which can be downloaded from msdn.microsoft.com/vfoxpro/downloads; this would involve installing the update to VFP5's Setup Wizard and rebuilding the distribution disks. if you are not now working under VFP 5.0a ( VERSION(1) should report Visual FoxPro 05.00.00.0415 for Windows) you need at least thge Setup Wizard updates, and would be far better off updating both your development system and the runtime distribution files to the files contained in VFP 5.0a

If you have not applied the latest DevStudio SP, which would update VFP5 to VFP5.0a, you can download the DevStudio Service Pack from the same site. You're looking for SP3 for DevStudio (VS97), not the VS6 SP3 patch which updates VFP6.