Abin, thank you very much for that information, that helps a lot. I was really having a hard time because I used a code example from codeguru.com on how to get the MAC Address of the PC. http://www.codeguru.com/Cpp/I-N/network/networkinformation/article.php/c5451 I used Method 3 (GetMACAdapters) and this includes iphlpapi.lib. Now DependencyWalker showed it relied on EFSADU.DLL which was not present on XP Home. So I was very confused. I now learned that although DepWalker lists EFSADU.DLL (which is called by IPHLAPI.DLL), this does not mean that it is explicitly linked. I must say that I have not really understood the concept between explicitly and implicitly linking, so I will try to learn about it. Thank you again, Tony