The first offline file sync operation fails when you pin an entry and then work offline on a client computer that is running Windows Vista or Windows Server 2008
Consider the following scenario. You have a client computer that is running Windows Vista or Windows Server 2008. You pin an entry on this computer, and then work offline. The pinned entry on the server side is modified. After the client computer works offline, the first offline file sync operation may fail without an error message. In this scenario, the offline file is not filled, and you cannot access the file correctly.
Note: The second file sync will succeed.
For more information on this issue, including potential causes, workarounds, and resolutions, see: Microsoft KB Article KB961529.