The Xbox One was not designed to support vertical orientation, according to Xbox senior director of product management and planning Albert Panello.
Speaking with GameSpot, Panello said players who choose to use the console in an upright position risk damaging it.
"We don't support vertical orientation; do it at your own risk," Panello said, noting that "it wouldn't be a cooling problem, we just didn't design the drive for vertical. Because it's a slot loading drive, we just didn't design it for both."
Panello said that Microsoft "found, interestingly enough, that 80 percent of people, believe it or not, have their Xbox  horizontally."
The Xbox One will launch on Nov. 22 in North America and in most European markets. The console will launch in Japan next year.
Both the original and slim models of the PlayStation 3 as well as the PlayStation 4 feature slot loading drives, although players can set the consoles vertically or horizontally without risk of damage.