As MSNBC reports,

A team of HHS officials is now working to reconstruct Tavenner's inbox by collecting emails from people she typically corresponded with and through other methods. They expect to recover "most, but not all" of Tavenner's emails, the letter adds.

"While we have not identified any specific emails that we will be unable to retrieve, it is possible that some emails may not be available to HHS, and we are therefore filing this memorandum," Kathleen Cantwell, a records management official at the agency wrote.

The excuse: