Ya might try to open a dos/command window when you can get TreeHouse and type in "Tracert www.gypoclimber.com" to get a baseline of what successfull contact looks like. Extend window to show all and ctrl + PrtScrn and paste inside of Paint to save.
Then; when not working; do same command and compare to snapshot. This could give clues if a different routing (tracert = trace route) makes the difference in success or not. You can also see if it times out at a certain point is the problem. If it takes too many 'hops' use the -h switch + a number of hops that you wish to confine the test by.
This will also give the ip address of the site, and y might try entering that in the ie window when not working to see if it is a naming problem/server down.