First thing to do:

Make sure you aren't using a VFP resource file (RESOURCE=OFF in Config.fpw)


>I am using the Interop Forms Toolkit vs 2.0. I have a number of .NET User Controls that I have wrapped in Interop user controls. I have them on VFP Forms. Basically they are new screens that are developed in c#. They are sized to take the entire surface of the form, the only other control is an off screen close button designed to work as the cancel operation.
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>Everything works fine initially. However under heavy usage we were having VFP crash seemly at random. Looking at the vfp9rerr.log we had a number of c0000005 errors. All of them at the time of launching one of the VFP\.NET forms. After some experimentation it seems that after repeated calling of any of the VFP\.NET forms the error is generated.
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>I have done some tests where I put the interop user control on a simple VFP form, have GotFocus call THISFORM.Release(). Then looped calling the form in the dev environment and received the crash. I have also had a case where I created a new form put the same control and had it work for 1000s of calls with out error. I have had 2 forms that seem to be the same with the same user control and one crashed and one worked. I have gone through property by property and found no significant difference. I have also opened the SCX of each form as a table, compared them, and found nothing.
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>I will continue to try to track down what is causing this, but does anyone have any ideas? Is anyone here using complex user controls with the Interop Forms Toolkit successfully?
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>Brooks