typo3: The requested page didn't have a proper connection to the tree-root!

Error after TYPO3 update from 4.2 to 4.5:

> Oops, an error occured! > The requested page didn't have a proper connection to the tree-root! > <br /><br />(Broken rootline (failed on page with uid 260))

Solution: TYPO3 backend -> install tool -> update database

From http://lists.typo3.org/pipermail/typo3-english/2011-March/074587.html