Dozens of iOS 5 users have been reporting issues with iOS 5 since it first came out and this week a new issue has begun to take form. Many users are now reporting that they’re receiving SIM card errors with iOS 5.0.1, even if they’re on a non SIM card network like Verizon.
Nobody is quite sure what is causing the error at this point, but it rebooting your iPhone seems to fix it temporarily. While the error is being displayed it is impossible to use any network connections such as phone, text messaging, or data communications so a reboot is basically required. Apple has not commented on the issue at this time so we can only hope that they get this problem resolved in the next iOS update, until then users will just have to keep rebooting to get rid of this incredibly annoying error message.