New iOS 5.0.1 Build 9A406 Intended to Fix 'No SIM Card' Errors on iPhone 4S
Yesterday, we noted that Apple had quietly released a tweaked version of iOS 5.0.1. The purpose of the tweak was a mystery given that the update was not being pushed to all users and only made available to those newly updating to iOS 5.0.1. The new version arrived as Build 9A406, and increment of one over the original iOS 5.0.1 release.
But based on a new Apple support document, it now appears that the updated build may have been designed to address an issue some users have been experiencing with SIM card-related errors. With the update affecting a relatively small portion of users, Apple may have elected not to push it out to all users in the form of an iOS 5.0.2 software update, and instead rely on those users who are having problems following Apple's advice and obtaining the new build through the restore process outlined as a solution for the issue.

Last month, some attention was turned on Apple as a quickly-growing thread in Apple's discussion forums revealed a number of users experiencing problems with either a "No Service" or "No SIM Card Installed" warning popping up on their iPhone 4S devices. From Apple's new support document:
In certain situations, iPhone 4S may have difficulty recognizing a micro-SIM card, resulting in the following behaviors:
- "Invalid SIM" or "No SIM Card installed" alert appears intermittently.
- Status bar displays "No Service" or "Searching" in a location with good network coverage.
Apple goes on to describe the recommended solution for the issue, which involves backing up and then restoring the device, an action that involves iTunes pulling down the new Build 9A406 of iOS 5.0.1 and installing it on the user's device. Once the device's system has been restored, the user can then restore content and settings from a backup.
1. Back up your user content and settings using iTunes or iCloud. See this article for more information.
2. Restore your iPhone 4S using iTunes.
3. After the process is complete, restore your user content and settings from your backup.
4. To confirm that you've successfully restored, verify that the version is now iOS 5.0.1 (9A406) in Settings > General > About.
Unfortunately, user reports on the new build appear to be mixed, with some users reporting that it does indeed fix their "no SIM card" issues while others have seen no improvement. It is unclear at this time exactly why results are mixed and whether the fix addresses only some subset of the root causes of the issue or if some other factor is in play. Consequently, we may have to wait for more users to try applying the update before drawing more specific conclusions.
Popular Stories
Apple's iPhone 17 Pro and iPhone 17 Pro Max models will feature a number of significant display, thermal, and battery improvements, according to new late-stage rumors.
According to the Weibo leaker known as "Instant Digital," the iPhone 17 Pro models will feature displays with higher brightness, making it more suitable for use in direct sunlight for prolonged periods. The iPhone 16 Pro and...
Apple is expected to unveil the iPhone 17 series on Tuesday, September 9, and last-minute rumors about the devices continue to surface.
The latest info comes from a leaker known as Majin Bu, who has shared alleged images of Apple's Clear Case for the iPhone 17 Pro and Pro Max, or at least replicas.
Image Credit: @MajinBuOfficial
The images show three alleged changes compared to Apple's iP...
Apple will launch its new iPhone 17 series this month, and the iPhone 17 Pro models are expected to get a new design for the rear casing and the camera area. But more significant changes to the lineup are not expected until next year, when the iPhone 18 models arrive.
If you're thinking of trading in your iPhone for this year's latest, consider the following features rumored to be coming to...
Just one week before Apple is expected to unveil the iPhone 17 series, an analyst has shared new price estimates for the devices.
Here are J.P. Morgan analyst Samik Chatterjee's price estimates for the iPhone 17 series in the United States, according to 9to5Mac:
Model
Starting Price
Model
Starting Price
Change
iPhone 16
$799
iPhone 17
...
An iPhone 17 announcement is a dead cert for September 2025 – Apple has already sent out invites for an "Awe dropping" event on Tuesday, September 9 at the Apple Park campus in Cupertino, California. The timing follows Apple's trend of introducing new iPhone models annually in the fall.
At the event, Apple is expected to unveil its new-generation iPhone 17, an all-new ultra-thin iPhone 17...
Apple is preparing to release iOS 18.7 for compatible iPhone models, according to evidence of the update in the MacRumors visitor logs.
We expect iOS 18.7 to be released in September, alongside iOS 26. The update will likely include fixes for security vulnerabilities, but little else.
iOS 18.7 will be one of the final updates ever released for the iPhone XS, iPhone XS Max, and iPhone XR,...
A new survey has found that nearly seven in ten iPhone owners in the United States plan to upgrade to an iPhone 17 model, signaling strong demand ahead of Apple's expected unveiling of the devices at its September 9 keynote.
Smartphone price comparison platform SellCell surveyed over 2,000 U.S.-based iPhone users in August to assess upgrade interest and brand loyalty before Apple's event....