Apps being downloaded by users from Apple’s App Store have been corrupted, with developers receiving complaints, reports The Register. As certain apps were downloaded from the App Store yesterday, the content was corrupted, creating errors that developers have been unable to fix.

Webpage bookmarking app Instapaper suffered from the issue soon after a new version was uploaded to the App Store, with creator Marco Arment receiving complaints that the app was crashing when launched. Arment discovered more than 20 other apps that were similarly affected, including Angry Birds in Space HD Free and Pinball Maniacs, with The Verge confirming many of these were failing on launch, often without an error message.

Another affected app, GoodReader, advised users to roll back to an earlier version of the app, and has carried out analysis that suggests the issue is affecting users who download app updates as soon as they’re notified about them.

Apple acknowledged the problem in a statement to AllThingsD, adding that it only affected a small number of users and has now been fixed. “We had a temporary issue that began yesterday with a server that generated DRM code for some apps being downloaded. The issue has been rectified and we don’t expect it to occur again,” the statement said.