Giving a little idea about background of fb.me, it’s a URL shortener started by Facebook. You can easily replace the first string ( facebook.com) with ( fb.me ). For an example if you are using custom name for your facebook Fan pages or profile page, instead of giving long URL, you can give fb.me/yourfbpagename .
Seems like Facebook people has taken it by heart and fb.me seems to be down for long. Many people started using fb.me to shorten their Facebook profile URL, for example if I have to share Shoutmeloud Fan page URL, I will share it using Facebook URL shortener and it will become http://fb.me/shoutmeloud and now this page is giving URL not found error.
Do let us know which URL shortener you are using and did you notice that Facebook URL shortener is down?
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