Updated: The Elder Scrolls Online item duplication bug forces Zenimax to shut down guild banks

An economy-crippling bug caused The Elder Scrolls Online to disable its Guild Banks on North American and European servers early Friday. Developer Zenimax has already put together a fix in the latest patch , but some users are complaining that they've been trying to warn developers about the problem for weeks.

The item duplicating bug became widely known after a thread about the problem hit the front page of Reddit. In that thread, redditor Mistress-Rarity writes that the bug is “so simple, in fact, that it is possible to do it by pure accident.” The game servers have been filled with “[p]layers in full legendary gear, billions of gold (From duping [materials] and selling them to vendors over and over), and so much more.”

A few videos showing how to duplicate items have been uploaded to YouTube, though the video's instructions can no longer be put to use since the Guild Banks were suspended. One such video is below:

Bugs that damage the fragile in-game economy are nothing new. More troubling, though, are the many users commenting that the bug has been widely known since before the game launched three weeks ago. A deleted ESO forum thread (cached here ) contains users posting that they first heard about the bug as early as this spring's beta test weekends or even last fall. Users claim to have reported the bug to Zenimax numerous times throughout development.

The ramifications for the in-game economy are pretty dire. If item duplication has been going on for this long, then those “illegal” items have already been used, traded, and sold throughout the economy. Trying to ban users might be hard if the bug is easy to do accidentally, and rolling back servers will result in a lot of players losing their hard-earned progress thanks to a few cheaters.

We've reached out to Zenimax Online for comment, and we'll report back when we have an update.

Update: A PR representative at Zenimax told PC Gamer, "Yesterday, we identified an item duping bug in ESO that some players chose to exploit. We acted quickly, and have since fixed the issue. We have a zero tolerance policy when it comes to abusing exploitable bugs, and those who were found doing so will have their game account permanently banned."