You attempted to discard a checkout on one or more files in a SharePoint document library, but you received an error.
A checkout discard might fail for any of the following reasons:
You may have lost connectivity to the SharePoint server.
To test your connectivity, try going to the SharePoint site in a Web browser.
The files may have been deleted on the SharePoint server.
A SharePoint workspace automatically synchronizes with its corresponding SharePoint site over brief, regular intervals, depending on network traffic. In rare cases, you might attempt to discard a checkout on files that were deleted on the SharePoint server during the period before the next synchronization.