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I have a c++ function that gets data and I called it from c#. The function gets a pointer to SAFEARRAY and poplate it with strings (using SysAllocString) Everything is ok, but the program is leaking memory. I did a little search and found that if I add this attribute to the method signature: [MarshalAs(UnmanagedType.SafeArray, SafeArraySubType = VarEnum.VT_BSTR)] out string[] strServerList I need to release it in c++ code (where it was allocated), so I created this function [DllImport("Native.dll", CallingConvention = CallingConvention.Cdecl, EntryPoint = "DeallocateExternal")] internal static extern void DeallocateExternal( [MarshalAs(UnmanagedType.SafeArray, SafeArraySubType = VarEnum.VT_BSTR)] out string[] strServerList); And in my dll i wrote this code void DeallocateExternal(SAFEARRAY** psa) { LONG cDims = SafeArrayGetDim(*psa); BSTR* pvData = (BSTR*)((*psa)->pvData); for (LONG x = 0; x < cDims; x++) { SysFreeString(pvData[x]); } SafeArrayDestroy(*psa); } But i got an exception: An unhandled exception of type 'System.AccessViolationException' occurred in Tester.exe Additional information: Attempted to read or write protected memory. This is often an indication that other memory is corrupt. What is wrong?

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