Apple's first update to its recently released iPhone software didn't go so well.
It withdrew the software update Wednesday following widely reported issues that left some unable to use their phone.
After the update, the phones were unable to connect to cellular networks and the fingerprint reader, a security feature, did not work.
"We have received reports of an issue with the iOS 8.0.1 update," the company said in a statement, adding it was "actively investigating."
Apple later released a statement saying that reinstalling the original version of iOS 8, known as iOS 8.0, would provide a temporary fix for the problem, and giving instructions to users how to do so using its iTunes service. Some users had posted on Apple's online support message boards that their phones were working again after completely resetting the phones.
It also said a new version of iOS 8, version 8.0.2, which it said will include a fix for the problem, will be available "in the next few days."
The iOS 8 software released last week, shortly before the latest iPhones, the 6 and 6 Plus, became available. Users have reported other issues, such as problems connecting to the phone using Bluetooth.