My iPhone 4 is pretty messed up after attempted jailbreak and restore

[sappy01]

My phone was jailbroken and then I updated my iPhone 4 to the newest 4.2.1 firmware. So the jailbreak went away and then I tried to rejailbreak it and it seemed fine and stuff except it just had the "connect to iTunes" picture and when I would connect to iTunes the only option I had was to restore my phone. It stayed like this for a while until I just held the power and home buttons and my phone restarted. It seemed fine except Cydia is just a white box and when I click on it it just pops up then disappears instantly. Same thing with Safari. I want to downgrade to the older firmware so I can just have my phone how it was but I keep seeing you need to have blobs and stuff and I have no idea what they're talking about. Is there anyway to downgrade or am I just gonna have to deal with this until the next iPhone update? Any suggestions?

Any help is greatly appreciated.

[Simon]

You have to use redsnow to boot tethered every time you reboot or turn off the phone.

[sappy01]

Okay thanks but what do you mean? Like where do I go or whatever? I'm sorry I don't know what you mean by "boot tethered."

[Simon]

You run redsnow again but only choose the option to boot tethered. 4.2.1 is a tethered jailbreak for iPhone 4.

[whereswaldo]

But there will hopefully be an untethered jb coming out soon for 4.2.1, If you have your SHSHs saved for 4.1, you should be able to downgrade and use greenpois0n to untethered jailbreak that

[sappy01]

Okay thanks both of you I understand what I have to do now. Once I did it and upraded Cydia it rebooted and I had to run redsn0w again and then once I downloaded Winterboard I had to do the same thing but when I did the phone is now just stuck at the apple logo.

[Simon]

You have to run redsnow again. Every time you reboot.