Microsoft is set to push out an Xbox 360 software update, but not all Xbox 360s will work with it.
The biggest part of the update will be the ability to run new high-capacity DVD media that was designed specifically for the console. Because it is a slightly new disc format, it won't work with just a standard DVD drive, which is what the early Xbox 360 units in 2005 and 2006 used.
"Following a recent update to our system software, we have become aware of an issue that is preventing a very small number of Xbox 360 owners from playing retail game discs," said Microsoft in an e-mail to Eurogamer.com.
"This issue manifests itself a as a unique 'disc unreadable' or 'disc unsupported' error on the screen."
However, the company is trying to make things right by shipping out a brand new Xbox 360 to those affected. "We are also able to detect this issue over Xbox Live and are proactively reaching out to customers that may be impacted to replace their console," the e-mail continued.
This isn't the first time Microsoft has pushed out mandatory updates to the system that posed undue hardship on console owners. A couple years ago the company introduced a massive software update that ate up more space than the memory that was available on low-end 360 systems. To resolve that, Microsoft sent out Memory Units to customers with an affected unit.
In addition to having a higher capacity, the new DVD medium is believed to have stronger piracy restrictions built in.