During his performance he said "F**k these computers," and then began jumping on top of display tables while rapping.
He apparently also stomped on at least five computers, according to a report from All Hip Hop's website.
Needless to say, the rapper's performance didn't last very long. Staff shut off his music and MGK was asked to get down, to which he did not respond politely.
"I'm not getting down," MGK said.
MGK did, however, get down and from the video below, it looks like the crowd was a little disappointed.
On Sept. 28, The Source held a private event at the Microsoft Lenox Square Store. We offer our stores as a venue for the community to use, and this event was not sponsored by Microsoft. While the artists behavior was appropriate for a concert, some of it was not appropriate in a store environment," Microsoft said in a statement to CNBC.
Watch MGK's brief performance here, be warned though, his lyrics aren't safe for work.
Correction:An earlier version of this story read that Microsoft hired the rapper Machine Gun Kelly to perform, however, the magazine The Source sponsored the rapper's performance, which was hosted at the Microsoft store.
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