I can only think that this is a security setting of some sort in each browser, (may be an add-on in Firefox).
We don't encourage short urls in these forums because we can't really tell where we are going to be taken to. The short url gives no clue, and can be used as a vehicle for suspect web sites.
But I don't know for sure, so I can't offer any fixes. However, I can suggest an add-on in Firefox called Long URL Please.
There's more about that, (an explanation), here;
http://www.networkworld.com/news/2010/051110-cryptic-shortened-urls-cant-hide.html
Does that help? May be others here will have better clues.
Mark
I'm not sure if this is a W7 problem or a PC problem, but I don't remember it happening before I upgraded to W7. If you use Twitter, you know they sometimes have shortened urls. When I click on them, they will not work. I simply get an error message stating "Oops! Google Chrome (or IE or Firefox) could not find ow.ly". Basically, the urls are in this form: http://fb.me/DbwCE8lA or http://is.gd/d2CPN or http://ow.ly/22RD9. What can I do to make these work again? I've tried turning off the firewall and changing to OpenDNS. Neither worked.

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