My guess would be a buffer overflow or similar issue, you are passing a string to your DLL that it is suposed to modify, but you are not telling it how long the string is.
Is there any documentation stateing how long the of a string it expects?
Having played around with some Windows system API calls in perl I've found that some will crash if the string passed to them is either too long or too small, you need to find what range you can pass in that is safe. Given that your passing a 1K buffer I'd guess your on the large size. How long is the expected result string? I'd guess that size times about 2 or 3 should be good, but if there is any documentation to lead you in the right direction that that over my wild guess work.

disclaimer: I doubt my advice will cause any problems, but were talking about calles into C, especaly calls modifing stings, any thing can happen, don't hold me responsible if any advice causes your computer to spontaniously explode or other catestrophic results.

In reply to Re: Win32::API giving a program error by Ven'Tatsu
in thread Win32::API giving a program error by Anonymous Monk

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