Why does free() keep triggering a breakpoint - c

Question

Can someone please tell me why my free() function keeps triggering a breakpoint? I then get a Microsoft Visual C++ Runtime Library error: Debug Assertion failed! Program: ... .exe, File: minkernel\crts\ucrt\src\appcrt\heap\debug_heap.cpp ... Expression: _CrtlsValidHeapPointer(block).
#include <winsock2.h>
#include <iphlpapi.h>
#include <stdio.h>
#include <stdlib.h>
#pragma comment(lib, "IPHLPAPI.lib")
int main()
{
IP_ADAPTER_INFO *pAdapterInfo = malloc(sizeof(IP_ADAPTER_INFO));
if (pAdapterInfo == NULL)
{
return 1;
}
ULONG size = sizeof(*pAdapterInfo);
ULONG * pOutBufLen = &size;
if(GetAdaptersInfo(pAdapterInfo, pOutBufLen) == ERROR_BUFFER_OVERFLOW) //When this error code is returned, the pOutBufLen parameter points to the required buffer size.
{
pAdapterInfo = realloc(pAdapterInfo, *pOutBufLen);
}
else
{
return 1;
}
if(GetAdaptersInfo(pAdapterInfo, pOutBufLen) == NO_ERROR)
{
while (pAdapterInfo->Next != NULL)
{
printf("%s\n", pAdapterInfo->Description);
pAdapterInfo = pAdapterInfo->Next;
}
}
free(pAdapterInfo);
getchar();
return 0;
}
SOLUTION: Ok, thanks for everyone for your responses. I fixed my problem with another pointer that I've called pAdapter:
int main()
{
IP_ADAPTER_INFO *pAdapterInfo = malloc(sizeof(IP_ADAPTER_INFO));
IP_ADAPTER_INFO *pAdapter = NULL; //for memory freeing purposes only
...
if(GetAdaptersInfo(pAdapterInfo, pOutBufLen) == NO_ERROR)
{
pAdapter = pAdapterInfo;
while (pAdapter->Next != NULL)
{
printf("%s\n", pAdapter->Description);
pAdapter = pAdapter->Next;
}
}
free(pAdapterInfo);