Gone, just gone with no explanation…
Check it out:

The IRS has submitted several sworn declarations to a federal district court in an attempt to explain the missing emails of former agency official Lois Lerner, as part of a case brought against the agency by a conservative watchdog group.

In the declarations, agency technology officials insisted they did everything they could to fix and recover data from the hard drive of Lerner, who is a central figure in the investigation into the agency’s targeting of conservative groups. However, they said their efforts were fruitless, and some of Lerner’s emails were lost.