I have iPhone 4 and my iOS is 4.10.01. I jailbroke it and installed a lot of applications. Being lazy to reinstall everything again every time after an upgrade, I decided to just leave it at iOS 4.10.01. It worked fine for a while but as new iOS versions came up, many of the applications I installed stopped working. I didn't care much for this as long as Cydia and my packages were working all right. However, at some moment the Cydia icon just disappeared, and I don't remember deleting it, though the installed packages continued working fine.
Yesterday, I wanted to update one of the packages as it wasn't functioning correctly. Searching the web for a method to restore Cydia without affecting applications suggested a method, which I tried. However, this failed and all the packages I installed were gone. Trying to reinstall them resulted in multiple errors being returned by Cydia.
I decided that it might be better to update iOS for the last time and start over, but that doesn't seem to be an option. The "update" option in Settings isn't there, and iTunes fails to be recognise the iPhone. Reinstalling iTunes multiple times does not seem to rectify the issue. I've also tried all my USB ports, along with iFunBox. As of now, I can browse media from my computer, but that's as much as I'll get.
What is causing me to not be able to restore my iPhone?