aylmerj

Thanks, Hyperhacker! I have had a few stack overflows, as well - but VB always (as far as I can see) seems to report these properly - so I don't think that's the problem here. This project was a conversion from Fortran - so instead of trying to work with big arrays of real numbers, I'm now breaking it all down into Types, each containing lots of little 3-element vectors. It's a long job, but the new code runs much more reliably - and goes about twice as fast, too...

Thank you both! I now suspect that many of my problems arise from the way(s) that I'm terminating the application. Many of the errors seem to occur at this point, now (and I had been thinking that I was fouling up the exit sequence by doing something illegal during the main execution). But that's not the whole story - I now have code which monitors every address passed to CopyMemory, yet the program can still crash after executing for a minute or two, without the monitor picking up any suspicious addresses... Matthew Curland's book sounds like a good idea - and probably cheaper than investing in VB2005, at this point...

Thank you both very much for your confirmation of my suspicions, and your guidance. The trouble is, I don't think the fault in my code causes a problem the instant it executes! The program van run round a near-identical cycle (with slightly different numerical values in the variables) several hundred times - and then Visual Studio crashes when the program is manually stopped. I'm trying to use Debug.Print to store the information that might help me track down the problem - but how can I see what addresses CopyMemory is actually writing to, and how would I know if one of them was illegal? Thanks again...

Can anybody help? I'm developing a VB6 application which involves a lot of matrix manipulation (loading a matrix using bits of other arrays, inverting the matrix, &c.) - but progress is slow, because VB6 keeps crashing at different points when I try to run the application. Sometimes it asks me to send an error report to microsoft (I must have sent over 100 in the past week), but sometimes it just quits without saying anything. I'm quite prepared to believe that this is because I'm overwriting some part of memory that I shouldn't be accessing (I'm using CopyMemory quite a lot to load the matrix) - but how do I find out if or where I am doing this? The program itself seems to work exactly as I would expect, and I can make an .exe file from it - but this also crashes randomly. I'm using XP for this work - if I try to run the application under ME (either from within VB6 or as an .exe file) it crashes immediately. Can anybody give me any guidance as to how to diagnose this? I'd be most grateful! I've attached an .exe file which shows the problem, but would gladly make the source code available to anyone who is willing to wade through it...PM3.exe