I first time faced this problem when I upgraded my iOS operating system from iOS7 to iOS8, I was unable to update my apps & even I was unable to download new apps from AppStore or from recent purchases.
First time I thought this is because slow WiFi but no avail after deleting old network & adding same network again doesn’t fixed my problem.
So I called up Apple Online Support Toll Free number what they said that this was happening because I installed new operating system via WiFi it may cause errors because of WiFi network loss or network interruptions. They said it is best way to upgrade iOS device operating system is via iTunes.
So here is how to fix this problem if you are getting error like unable to install updates this time, unable to download app at this time, unable to purchase or App doesn’t exist on AppStore:
Note: First things first backup your iOS device using iTunes before following below steps.
Prerequisite: Before moving forward update your Mac to latest updates for OSX & iTunes software using Mac App Store. Only if all apps are up to date with latest versions you can move forward.
Step 01: Open Settings App: Go to General > Reset > Reset All Settings
Step 02: Now tap on ‘Reset All Settings’ button it may ask for device security code or password enter that then confirm again by tapping on ‘Reset All Settings’ button prompt.
Step 03: Your device will reboot with reseted settings to factory default system wide.
Step 04: Now Add WiFi network again to your wifi settings tab & If asked enter your AppStore password, Now try to update your apps from AppStore.
I am 100% Assure that you will able to update your Apps & download new one with this tweak.
Solution 02: Another solution would reseting your iOS device to it’s factory settings
Step 01: Check if your OSX & iTunes is up to date using software update. Use latest software only.
Step 02: Connect your iOS device to iTunes through your computer USB cable.
Step 03: Select your device in iTunes & under Summery pane click on Restore button for your device.
Step 04: Confirm Restore by clicking Restore again to restore your device to factory settings and delete all data and content. iTunes will download the iOS software file and restore your iOS device.
Step 05: After your device is restored your device will restart & will display ‘Slide to Setup’ button on screen. now you have to follow on screen instructions to set up the device.
Step 06: Now you can restore your backup Apps, Books & Music to your device using iTunes
Solution 03: If solution two doesn’t work then last resort is you can put your iOS device in recovery mode and then restore it with iTunes.
Step 01: Connect your device to your computer and open iTunes.
Step 02: Press and hold both the Sleep / Wake and Home button for at least 10 seconds, and don’t release until you see the Apple logo. Keep holding until you see the recovery mode screen. It will look something like below image.
Step 03: When you see the option to Restore or Update, choose Restore. Wait while iTunes downloads the software for your device.
Note: If the download takes more than 15 minutes and your device will exit recovery mode, you’ll need to repeat these steps and choose Restore again when iTunes completes downloading iOS Software.
Step 04: Follow on screen instructions shown by iTunes & after iTunes completes restoring your iOS device your problem should be solved automatically. Hope it helps.
Hope it helps,
Thanks & Regards