Networking workgroup computers

[CrystalClear]

I have three computers networked in a workgroup. One of the computer cannont be accessed. The other two computers are accessible on the network. I check the connections and all ok. I need this computer back on the network. Pls help  http://images.thetechguide.com/forum/public/style_emoticons/<#EMO_DIR#>/sad.gif\' class=\'bbc_emoticon\' alt=\'\' />

[WyWy]

Is the third computer visible in the workgroup? If it is not make sure it is a member of the work group.
If it is visible do you get an error message when tring to access it? If so make sure that the folders you want to share have been set to network share.
You may try creating a guess account on each computer and using it to access each computer in the work group.