The company that managed Hillary Clinton's private email server, during her tenture as U.S. secretary of state, said it has "no knowledge of the server being wiped," which means that the tens of thousands of e-mails that Clinton deleted could be recovered.

Clinton has faced ongoing criticism since it was discovered that she may have stored classified material in a private email server while she was working under the Obama administration. Critics say this could have put national security secrets at risk. Her use of the server, which was maintained by a small Denver company and stored at a secure data center in New Jersey, also prompted an FBI counterintelligence investigation that has since came to an end.

In wake of the controversy, Clinton and her campaign maintained that the 2016 hopeful deleted her personal correspondence, which led some to believe that 31,000 e-mails were gone forever.

However, The Washington Post revealed over the weekend that Clinton's deleted emails may actually be recoverable by technicians since the server was not wiped clean. Deleted emails can still be restored from a server depending on the condition of the server, explained the paper. Emails can only be permanently deleted after a server has been wiped by overwriting the underlying data with gibberish.

According to Platte River Networks, the ­Denver-based firm that has managed the system since 2013, the process to wipe the servers did not occur.

Platte River has no knowledge of the server being wiped," company spokesman Andy Boian told The Washington Post. "All the information we have is that the server wasn't wiped."

Last week, the former first lady said that using a private "homebrew" email server was a "mistake" during an interview with ABC News' David Muir. She also acknowledged that she should have used different accounts to separate her work and personal business.

"That was a mistake. I'm sorry about that. I take responsibility," she said.