Skype
If you and the person you're trying to help out both already have Skype accounts, you can also use it for screen sharing. Unlike some of these other solutions, you won't be able to control the remote computer; you're just limited to seeing what the other person is doing (see Figure 5).
Initiate a Skype call with your contact, and then have the person on the remote computer click the Plus (+) button or select the Conversations menu and choose Share Screen. The other person will be able to select either the entire screen or just a single window, and you'll be able to see exactly what he or she is doing. You'll also have an open audio connection, so you can help troubleshoot, and you can even carry on a two-way video chat at the same time.