If you have an older iPhone, iPod or iPad (3GS, 4, 3G, 2G, and so on), and an iMac running a newer version of macOS in 2017, you might have figured out already how hard it is to jailbreak/restore a CFW on these legacy devices. Most of the existing tools like RedSn0w would give errors like "USB Communication Problem" or simply "Exploit Failed!" everytime you try to put the device in PWNED DFU MODE using Limera1n exploit.
If you're a windows user, you might be in luck, as some of the tools including RedSn0w appear to be working on Windows with no big problems (especially on older versions of Windows, like Windows 7). macOS users are not that happy. Due to some bizarre reason, most of the tools made in the days of these legacy devices that are no longer updated or maintained are simply no longer working in a way or another.
A few days ago I was pointed to iPWNDFU which is a modern tool created by axi0mX that can, amongst other things, put your legacy device in PWNED DFU mode so that you can Jailbreak it, restore a CFW for Hacktivation, or downgrade it with SHSH blobs. So in this video, I decided to show you how to use axi0mX's tool to get an iPhone 3GS (or any other limera1n device) in PWNED DFU mode.
How to put the device in DFU Mode?
To use the tool, you need to first connect the device in DFU mode. That can easily be done by connecting the USB cable (with the device turned off), holding POWER and HOME Button until the apple logo disappears and then a few more seconds, then release the POWER button while keeping the HOME button pressed for 10 more seconds. You should now be in DFU mode. Remember, in DFU mode there is nothing on the screen. If you see the old iTunes logo and a USB cable on the screen, you ended up in Recovery Mode which is a different mode than the one needed. Try again.