I have been answering this question a lot lately, so I thought I would take a moment and document it.
In the past, PRE V5R17, you could change the foundation location on a client by modifying the xml in the Machine.config file. The file is located in the "C:\WINDOWS\Microsoft.NET\Framework\v2.0.50727\CONFIG" directory. That location could change based on what version of .NET you had installed and working with SmarTeam.
It has now been moved, to what I believe is a much better location. You can find the settings in the file: "SmarTeam.Std.LocalConfiguration.dll.config" in the "C:\Program Files\SMARTEAM\Bin" directory.
This config file is also an XML file and you will need a text editor or your favorite xml editor to make the changes. WARNING! Don’t try to use MS Word or Wordpad.
Look for the machine name, or IP address, of your foundation server in the config file. The XML will begin with URL -> <Url>tcp://m90-tech8:5606/
You need to change the Machine name between the forward slashes (//) and the colon (:)
Also note that there are 3 places in the file where this needs to be changed.
So there you have it… If you ever need to point your SmarTeam client to a new, or different, foundation server just follow the directions above.