Conflicting accounts of when data was removed from Hillary Clinton's private server indicate copies of emails known to contain classified information may reside on a device other than the one presently in FBI custody.

She may have printed 55,000 pages of emails for submission to the State Department from a different device than the one presently in FBI custody.

Platte River Networks, the company that managed Clinton's email network after she stepped down from her post as secretary of state, indicated it transferred data off the original server in mid-2013.

An attorney for Platte River said there is likely "no useful data" remaining on the server.

But the Clinton campaign has suggested the former secretary of state did not erase emails she deemed personal until January of this year, raising questions as to where the emails were located when her staff sifted through them to determine which were related to her government service.

A Clinton spokesman did not return a request for comment, nor did an attorney for Platte River Networks.

The discrepancy further obscures the timing of Clinton's decision to erase 30,000 emails she claimed were unrelated to State Department business.

Dr. Marcus Rogers, head of computer information technology at Purdue University, said the fact that the data was migrated off Clinton's server in 2013 doesn't mean it was erased from the server at that time.

"There's pretty definite time stamps when you move information from one computer to another," Rogers said. "Somebody knows exactly when this happened because those time stamps are there."

Chris Weber, a security expert who co-founded Casaba Security, agreed the data migration might have just been a way of making copies of the emails on Clinton's server, not deleting them.

"If I move to a new home, I've migrated to a new home, but it doesn't mean I don't have things in the old home or the old home isn't there anymore," Weber explained. "So there may potentially be two copies of [the emails] at that point."