Downgrading from iOS 5 to 4.2.8

[Deteribl]

I have iphone 4 i need help on how to downgradefrom 5 back to 4.2.8 I have shsh blobs on cydia but im not sure how to use them i have tried TU server but have had no luck if anyone has any advice please let me know

[i.Annie]

I hear on the Verizon iPhone you can't downgrade with or without SHSHs. I mean, technically you can with SHSHs but the phone will not activate. Therefor, you're forced back up to iOS 5 anyway.

Edit: you could try though. Use TinyUmbrella, open it and click Save SHSHs to pull them into TU, then start the TSS Server, then Shift+restore to 4.2.8. The restore will go through, the phone won't activate in iTunes though. At least that's what a couple of users around here have reported.

[TVC430]

I hear on the Verizon iPhone you can't downgrade with or without SHSHs. I mean, technically you can with SHSHs but the phone will not activate. Therefor, you're forced back up to iOS 5 anyway.

Edit: you could try though. Use TinyUmbrella, open it and click Save SHSHs to pull them into TU, then start the TSS Server, then Shift+restore to 4.2.8. The restore will go through, the phone won't activate in iTunes though. At least that's what a couple of users around here have reported.

Just out of curiosity, can you activate if you get an older version of iTunes installed?

[i.Annie]

I don't believe so. The concept of it is that once you upgrade to iOS 5, your baseband is upgraded. With that new baseband, it prevents activation of your device on anything below iOS 5.

[Deteribl]

Well i will try and let u know thanks for the help

[mlee19841]

Won't work once u update to ios 5. Ur stuck if u have a vzw iPhone. I had my shsh blobs saved. The phone downgraded fine but would not activate. I tried different iTunes from 10 all the way to the newest one and even older ones. I tried jailbreaks to get past it. Still nothing. So until someone has a idea. Once u upgrade ur stuck.