On Fri, 26 Feb 2016, Jules van der Toorn wrote:

> When i build the simple code he gave in his guide, it works great. However
> if i use my (working with the dynamic library) mail receive program, MSVC
> gives an error: first it says "program.exe has triggered a breakpoint", and
> if i click continue it says: "Debug Assertion Failed!" "Expression:
> _CrtIsValidHeapPointer(pUserData)"

I'm afraid that is too little information for us to do anything with.

Can you run it through a debugger and tell us more precisely where it crashes
and what the contents of the important local variables are?

Honestly though, I would rather suspect a flaw in your build. Like not using
the correct memory model or something in one of the libs you use.

-- 
  / daniel.haxx.se
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