Symptoms
Microsoft OneNote 2010 clients may be unable to synchronize with a SharePoint Foundation 2010 server. This issue usually occurs when the SharePoint Foundation 2010 server is under heavy load.
Resolution
To resolve this issue, apply the following hotfix package:
2479788 Description of the SharePoint Foundation 2010 hotfix package (sts-x-none.msp): February 22, 2011 Note After you apply this hotfix package to the SharePoint Foundation 2010 server, you should also apply the hotfix package that is in Knowledge Base (KB) article 2504133 to the OneNote 2010 client.