If you are installing the Twitter application on Facebook:
http://apps.facebook.com/twitter/
You may be experiencing problems attaching the account. We're aware of the issue and are working on a fix. Until then, please try the following hack first:
If none of these work, you may want to try an alternative app, called "Selective Twitter":
http://apps.facebook.com/selectivetwitter/
Also, become a fan of the Twitter Facebook page for more Facebook related updates:
http://www.facebook.com/apps/application.php?id=2231777543
Sorry for the inconvenience!
Twitter Support
UPDATES:
May 18, 2010 – EP: Fix shipped! Twitter will now update your profile and wall on Facebook, but not your status. Click here for more information.
May 5th, 2010 -- TH: A fix should be shipping shortly.
April 20, 2010 – LE: Some users are reporting instances of this issue that are not solved by altering their privacy settings or the steps above. We are actively investigating these cases and working on a solution for all affected users.
February 23, 2010 – EP: If you are experiencing issues in having your Tweets delivered to Facebook, please try the steps above. You may also want to review your privacy settings in Facebook. Some users report that the Twitter app appears under the "never allowed to post any stories" area, and that removing it and setting "Posts by Me" to be viewed by everyone fixes the issue.
February 02, 2010 – TH: We are continuing to investigate this issue, pls bear with us!
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