Apple has announced that they fixed all security bugs that TaiG had exploited to jailbreak iOS 8.4. It seems users need to wait for a long time for official iOS 8.4.1 jailbreak solutions. However, we can get back to iOS 8.4 quickly by downgrading iOS 8.4.1.
Downgrade 8.4.1 to 8.4
Firstly, you need to turn off Touch ID/Passcode (Settings > Touch ID & Passcode) and Find My iPhone (Settings > iCloud > Find My iPhone to off).
- Download iOS 8.4 firmware or any iOS versions compatible to particular device from here: http://www.ipswdownloader.com
- Connect your devices (iPhone, iPad) to PC, launch iTunes
- Backup all your Data including photos, musics, videos,….
- Get DFU status: You need to get your iOS device to DFU status by holding the 2 buttons (Power and Home) in 10 seconds roughly. And then free the Power button and keep holding Home button until iTunes get connected to your iPhone. Click on OK button.
- From iTunes, head over to the device Summary page. Press and hold Option + Alt on Mac keyboard or Shift in Windows and choose Restore iPhone… (iPad/iPod touch…).
- Click on the Restore and Update button to continue.
- Select iOS 8.4 Firmware: You should now see a prompt to browse and select the iOS 8.4 IPSW file you downloaded.
- Click on update button to get back iOS 8.4
- The further automatic processes will takes a few minutes to be accomplished. iPhone, iPad or iPod Touch will reboot themselves and you get back iOS 8.4 and downgrade iOS 8.4.1 successfully.