I suspect the medical application expects to be on top, and the programmers didn't adequately test for the possibility that an astute user presses Alt-Tab. I don't recognize the DLL, which is not found, so I suspect that it corresponds to the medical software - and the error messages likely origate from it, too, and not from VFP. It would be interesting to try the same manipulation with other applications, e.g., switch with Alt-Tab to Microsoft Word.

>We have an NT4/SP6 box running a proprietary medical software application side-by-side with our VFP application. The medical software does some impudent things, like apparently hooking messages to other applications so that whenever they minimize or otherwise yield foreground, it asserts itself to foregroud and re-maximizes to basically function in kiosk-mode (i.e., you then have to hit alt-tab or alt-esc to do anything else on the system).
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>The _weird_ thing is that sometimes when you do a mouseover on the VFP app (when it has been brought to foreground with alt-tab, for example), the system will start throwing up "Unable to locate DLL" messages (this appears to be a sysmodal messagebox). It always says it cannot find jvm.dll. Once it starts doing that, you're sunk... i.e., it then happens with every subsequent mouseover event occuring with the VFP app until you exit the medical application software and restart it, then things work fine.
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>Has anybody else seen behavior like this? Any ideas or explanations? Thanks!