Trouble upgrading 3GS to 5.0 using RedSn0w

[Weavel33]

Hi, I attempted to update my custom 4.3.3 (created in Pwnage Tool) 3GS to 5.0 today using this tutorial. iClarified - iPhone - How to Jailbreak Your iPhone Without Updating the Baseband (Mac) [5.0]

However, after creating the custom IPSW, putting my phone into pwned DFU mode or whatever, and selecting the IPSW to be used, iTunes told me that my phone "isn't eligible for the requested build."

How can I resolve this?

If it's of any value, I'm trying to jailbreak and preserve my baseband (05.13.04) in order to unlock with Ultrasn0w, and I'm using iTunes 10.5 on a Snow Leopard iMac.

Thanks

[Simon]

Open tiny umbrella
Click on advanced
deselect the box that says "set hosts to cydia on exit"
Close tiny umbrella and proceed with the custom firmware restore

[Weavel33]

You're a life saver! Although I don't understand how tiny umbrella affects anything when it's not running.

[Germanese]

Read the check mark.

What it did is modifying few lines on what server itunes should use to get the shsh.
So if checked it uses the Cydia Server, if unchecked it uses the Apple server.
If clicked on the SHSH server from Tiny Umbrella it uses TinyUmbrella as its SHSH server.

Wrong server wrong keys, cant update.

[iYeow]

+1 to Germanese, all IOS 5 restore needs verification of apple server.