Over the air updates (OTA) are very important and helpful to your iOS. They keep up to date iOS with all the latest software developments, and other iOS updates. These OTA are relatively quicker and take less bandwidth. You can access them from settings, by tapping general and then software update. For over the air updates, you should have iOS 5.0.1, Wifi, and iOS device battery should be at least 50% charged. When you meet all these requirements you can get over the air updates on your iOS device. 3G and EDGE network are not supported for OTA updates. Also if iOS device is running beta version, it will still be unable to launch OTA updates. While having all the requirements, if you still unable to access OTA updates, follow these steps.
- You can turn on or off wifi once again to see if that works. It may solve your issue.
- Restart your iOS device, or plug it into power source. Because battery charging less than 50% restrict these OTA updates.
- Reset network setting is the last option, but it will definitely solve the issue.