The iPhone Dev-Team has recently updated redsn0w, adding support for Windows computers and fixing a GPS issue that occurred with certain iPhone 3GS handsets. Like the previous version of redsn0w (which is Mac only), this new version allows users to apply a tethered jailbreak to an iOS 5 device, and apply the software update to an iOS device while preserving its baseband.

As outlined by the iPhone Dev-Team:

We’ve released version 0.9.9b6 of redsn0w, with both a functional fix and cosmetic fix for iOS5 jailbreakers. For iPhone3GS owners with the 06.15 baseband, this redsn0w eliminates the network crash you saw when using Location Services in iOS5 (in fact, you don’t even need to disable Location Services anymore during the initial setup). The cosmetic fix is to the visual countdown you see when going into DFU mode.

It’s okay to re-run this redsn0w over an existing device jailbroken at iOS5. Just choose “Jailbreak” again and de-select Cydia (in other words, all the checkboxes will be unchecked).  If you are lucky enough to have an old-bootrom iPhone3GS, please pre-select the IPSW first (redsn0w can’t yet auto-detect the FW version of your old-bootrom 3GS if it’s already been jailbroken).

Do remember that redsn0w’s jailbreak solution is “tethered,” meaning you’ll have to connect your jailbroken iOS device to a computer, launch redsn0w and boot tethered in order to regain jailbreak functionality if a mobile device powers off. The good news is that an untethered solution should be available soon (we’ll keep you posted on that front).

You can download the latest version of redsn0w over at the iPhone Dev-Team’s blog. Below, we’ve got a couple of guides that might help you out when it comes to jailbreaking and unlocking under iOS 5.

How to jailbreak iOS 5 using redsn0w

How to update to iOS 5 while preserving your baseband