es1968 wrote: how to let it enables the GUI ? It doesn't. Services run in the background and are prevented from having a Windows front end, specifically because they do not have user interaction. You can provide an interface so a normal GUI based program can pass information to and from the service, but that's all that is allowed. One of these days I'm going to think of a really clever signature.

You can certainly split it up, yes Some of the MFC classes are now shared with ATL, I'm not too sure about CSocket - I would guess not very easily, looking at the afxsock header

cmk, Thank you very much, Eyal

Rajesh, Thanks a lot, Eyal