Democratic presidential candidate Hillary Clinton joked Tuesday about the fact that her private email server was wiped clean.

“My personal emails are my personal business, right?,” Clinton told a reporter while stumping in Las Vegas, noting that she turned over a server that had been in the basement of her New York home to federal investigators. The server, which had been stored by the tiny Platte River Networks IT firm since 2013, was “wiped” clean of information, according to a Clinton lawyer. It is unclear if a backup server exists.

“What, like, with a cloth or something?,” Clinton cracked, referring to the fact that the server was wiped.

“I don’t know how it works digitally at all,” Clinton said.