The Windows version of IOS untethered jailbreak 4.2.1 soon

The Dev-Team is working on the Windows version of Redsn0w untethered to jailbreak 4.2.1 using IOS IOS SHSH 4.1, using the Monte exploit (which is not exactly an exploit, but rather a method.)

It will be quite slow and can not use RAM, but the important thing is that it works but is slow.

You need to have the 4.1 IOS SHSH stored in Cydia.

Here's everything you need to know about SHSH.

If you are a Mac user, here's the tutorial to jailbreak 4.2.1 untethered to iOS