Thousands of gamers have been cut off from Microsoft's online gaming service Xbox Live for modifying their consoles to play pirated games.

According to various online reports, 600,000 gamers may have been affected until now. Microsoft talks about a "small percentage" of the 20 million Xbox Live users worldwide that have been banned. The reason is that these gamers had modified their Xbox 360 console. This violates the service's "terms of use" and would result in a player being disconnected, according ot Microsoft.

Affected users no longer have access to Xbox Live, although their Xbox 360 game device is still working.

"To help protect that experience for our customers, the Xbox LIVE Enforcement team monitors the service for behavior that violates the Xbox LIVE Terms of Use and Code of Conduct. Violations of the Xbox LIVE Terms of Use and the Code of Conduct can result in a variety of actions, up to and including a permanent suspension of a console from connecting to Xbox LIVE," reads Xbox LIVE policies text.

Microsoft's Larry "Major Nelson" Hryb had warned Xbox Live users last week.

"We?ve been actively banning consoles from Xbox LIVE that have been modified to play pirated games. Our commitment to combat piracy and support safer and more secure gameplay for the more than 20 million members of our Xbox LIVE community remains a top priority. All consumers should know that piracy is illegal, and that modifying their Xbox 360 console to play pirated discs, violates the Xbox LIVE terms of use, will void their warranty and result in a ban from Xbox LIVE. The health of the video game business depends on customers paying for the genuine products and services they receive from manufacturers, retailers, and the third parties that support them. This would also be a good time to remind you that the warranty on an Xbox 360 console is not transferrable and if you purchase a used console that has been previously banned, you will not be able to connect to Xbox LIVE," Nelson wrote on his blog.

Many gamers modify their consoles by installing new chips or software that allows them to run unofficial programs. Some chips are specifically designed to play pirated games. According to Microsoft, when a console is suspended from accessing the service, it will display the following message:

"This console has been banned for violations of the Terms of Use. To protect the Xbox LIVE service and its members, Microsoft does not provide details about console bans. There is no recourse for Terms of Use violations."

Consoles can be suspended from Xbox LIVE for a number of reasons including, but not limited to:

- Console tampering: Physically opening the Xbox and modifying it to play illegitimate software.
- Online fraud: Attempting to social engineer users, take over Xbox LIVE accounts, or other fraudulent activities.
- Repeat egregious violations: Multiple actions taken on accounts on the console by the Enforcement team for disrupting the service or impacting users.

In addition, there are some reasons that a console could be permanently suspended from the service, Microsoft added.

The company did not provide details on how the Xbox team detects modified consoles.

"There are many factors that lead to the suspension of a console and we do not publicly disclose any of those details," the company said.

Earlier this month, Microsoft also released an update for the Xbox 360 that made unauthorized third party storage devices cease to work with the console. Apparently, 'authorized' storage devices extend as far as Microsoft's own products.