After Apple released iOS 6 beta 4 yesterday, we started getting flooded with emails and tweets concerning an "Unable to Check for Update" error that was occurring when trying to install the new beta over-the-air (OTA). If you're a developer trying to install iOS 6 beta 4 and you keep getting that error, here's what you can do...
Turn off Wi-Fi
This seems to be the simplest, quickest solution if you're experiencing the "Unable to Check for Update". Just go into Settings, turn off Wi-Fi, go to General > Software Update, and the update should appear.
You can then turn Wi-Fi back on to download and install iOS 6 beta 4. Thanks [@m4tt]
If that doesn't work, you can start the escalation...
Reboot your iPhone, iPod touch, or iPad
Several developers have also told us that, after getting the "Unable to Check for Update" error, they rebooted their iPhone, iPod touch, or iPad, and the OTA update then began to work properly.
If you're getting that error, try a simple reboot first. Then redo the OTA update process:
- How to manually update to iOS 6 beta over-the-air (OTA)
A large portion of developers have also told us a reboot didn't help them at all. So, if after doing a reboot, you're still getting the "Unable to Check for Update" error, you might have to forgo OTA and do your update the old fashioned way...
How to install iOS 6 beta 4 via iTunes or Xcode
Sure, there's no beating the speed of OTA's bit-differential/delta format, and the efficiency of installing-in-place, but if you want the update done now, you'll have to turn to your old friends iTunes or Xcode.
You'll have to backup your device to iTunes (or do a clean install), and make sure your UDID is properly provisioned with Apple's developer portal, but it's your best bet to beat the pesky "Unable to Check for Update" error get iOS 6 beta 4 up and running.
More help
If you're having any other problems, or just want to discuss the issue and get more personalized help, check out our:

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