I'm new to websphere. I installed websphere on my windows PC and click on the start server start menu option. The DOS prompt appears with server startup messages. When I select Samples Gallery (http://localhost:9080/WSsamples) I'm getting page not found (404).
Is this WAR deployed inside an EAR? First, check the log file and verify the server started and there were no serious errors (small errors are ok believe it or not).
Next log in via the WebSphere Admin console which should *always* be available if the server successfully started. The port can change depending on the settings you used when you installed the server or created the profile but it is most often found at:
Assuming you're on the server computer, localhost should work fine. Once in there, look at a list of deployed applications. If the 'Samples' package is not in the list or included inside some other component, you will need to add/install it.