forums.wsusoffline.net

It is possible to have one client installation on server and clients can do the update through the server client installation?

If you share the ./client subdirectory on the server (readonly is OK), you can execute it from the clients, provided it does run from an assigned drive letter and not directly from UNC path. AFAIK the GUI tries to assign automatically.

Note that usage is against the philosophy of WSUS Offline Updater. Maybe you should think about setting up a real WSUS.