Debugging a Web service on a remote machine works in almost the same way as debugging a local Web service, but there are some initial steps that you must take in order to make everything work properly.
First make sure that the Visual Studio remote debugging components have been installed on the machine hosting the Web server. Chapter 15 discusses remote debugging setup in some detail. To grant access to the user who is performing the debugging, you must add that user in the Debugger Users group on the remote machine. Finally, as discussed in the "Debugging Preparation" section at the beginning of this chapter, you also need to add the same user account to the Administrators group on the remote machine. This is because, by default, the ASP .NET worker process runs as a SYSTEM process, and you're not allowed to debug a process running under another account unless you're an administrator.
After this, you should be able to debug the remote Web service almost as though you're debugging a local Web service. There are, however, a few differences, such as not being able to invoke Web service methods from the test Web page.