Two European carriers are warning iPhone 4S users not to upgrade to iOS 6.1 until Apple fixes bugs - and IT departments are reporting problems too.
Carriers say users have been experiencing problems with internet access, calls, texts and Exchange access since the upgrade was issued on January 28.
"Some customers may occasionally experience difficulty in connecting to the network to make or receive calls or texts or to connect to the Internet. Apple is working on a solution to their software issue. These connection problems are intermittent," warns Vodafone.
"While Apple’s investigations continue, we would recommend that anyone who has not yet installed iOS 6.1 on their iPhone 4s should delay doing so until Apple has confirmed that their problem has been fixed."
And 3 Austria has put out a similar message. "The update of the iPhone 4S on iOS 6.1 may cause connection problems," it says. "We have reacted promptly and are collaborating with Apple. For this reason, we recommend not to install the update."
Meanwhile, the update is causing problems for others too. Organizations connecting to an Exchange server for mail and calendar services are seeing sharp spikes in server logging, apparently because of a bug in the way calendar invites are handled.
"I had a user upgrade to 6.1 and immediately after he finished, his phone/IPAD started causing excessive logging on the exchange server," one user reports on a Microsoft forum. "His device caused over 50GB worth of logs for that particular database."
Apple's reported to be working on a fix, but in the meantime one user suggests deleting and recreating the mail profile, saying this eliminates the problem. Others are simply blocking iOS 6.1 from accessing Exchange altogether.