This TinyUmbrella 4.2.1 tutorial will help you backup iOS 4.2.1 SHSH blobs. Apple has already released iOS 4.3 Beta 1 and if you upgrade to it, you won’t be able to restore to iOS 4.2.1 if you don’t have iOS 4.2.1 SHSH blobs saved.
Here are step by step TinyUmbrella 4.2.1 instructions to backup your blobs:
Step 1: Download TinyUmbrella
- Windows: tinyumbrella-4.21.02.exe
- Mac OS X: TinyUmbrella-v4.21.02.pkg
- Linux / Ubuntu: tinyumbrella-4.21.02.jar
Step 2: Connect your device (running iOS 4.2.1) to the computer via USB
Step 3: Launch the downloaded TinyUmbrella
Step 4: You’ll see the connected device in TinyUmbrella sidebar (top-left). Select your device (click on it).
Step 5: Click on Save SHSH to start saving your SHSH blobs
That’s all you’ve got to do. TinyUmbrella will now save iOS 4.2.1 SHSH blobs. This will help you restore custom IPSW to iOS 4.2.1 and may be crucial to jailbreak iOS 4.2.1 or later.
