Working from within Windows 8 OK I just tested it from within Windows 8 and that work with the DISM command well. The full time for to create the W2G drive was need 6 minutes and an external USB 3.0 drive with 750GB Hdd.
Said the above, I think I could build an Windows to Go drive using Pro ISO as well. Will do that tomorrow evening.
I am confused by your usage of the drive letters x: o: b: c: I assume is the systemroot step 6 always ends this way: When I list partitions I can clearly see that step 5 was successful.
To create an Windows To Go Drives differs a lot from normal installation. You create those drive from within running Windows 7 or 8 and that means that drive C:\ is used by the Windows version you run and therefore could not be used as a drive letter on the USB device. Here you could only use drive letters which are free and unused by the running Windows system. The drive letters you'll use on the USB Storage, will change to drive C:\ after booting form the newly created Windows To Go drive and the other drive letter/partition (350MB) you'll will not even see in Windows Explorer from within running W2G. While creating the Windows To Go drive, ALL partitions on the USB device need to be removed first. That is to be done with the command: clean (no. 4 on the list above). After that you start to create 2 new Partitions: Partition 1 with a size of 350MB partition 2 with the rest of the available space or limited to a size of min. 20GB, I use 200GB on the 750GB USB Drive which I use for that. It's important that the first partition is (Partition 1) will be the 350MB partition. The partition scheme is the same as in an normal installation of Windows 8. According to your screenshot, you didn't had deleted the old partitions form your USB Drive. That will NOT work. You also can NOT install W2G on an internal HDD which contains already any partition and it looks like that you just try to do that! THAT WILL NOT WORK either! If you use an internal HDD, which you could, you have to do exactly the same as on an external USB Drive which means ALL of the data on that internal HDD will be deleted. If you create using an internal HDD you have to use the BIOS Boot Manager of your MB for to boot for the W2G drive using the assigned "F" Key. You could even not use the Windows Boot Manager!
I used a code I found on a website (posted info in another thread here @ MDL) & created mine (Win8 x64) on a WD my passport USB 3.0 drive (also created in Win7), works great. I also shrank & partitioned that drive so I have storage outside the OS partition.
I normally use 64bit on my computers only. For the W2G Drive i Used 32bit for computers which didn't have enough performance! The 750GB i installed as 64bit and places for the 350 MB + 200GB for W2G. rest I use for to carry what I need to take with me. The procedure I used, as described in my OP, works on Windows 7 and Windows 8 without any problems.
It looks like he used an HDD with alraedy existing min. 3 partitions maybe also an Windows installed.
In reality, I gave up with USB Sticks. None of those I used were working even if accepted by Windows. It were Kingston and Sun which were accepted but working correctly and PQI, Apacer, Transcent were deny directly. With HDD: NO problems. I use 1 Acer USB 3.0 500 GB and 2 Smartdrive USB 3.0 Cases with 1 Hitachi and 1 Toshiba HDD, both 750GB as external HDD USB 3.0 Drives. 32GB wouldn't be enough anyway for what I need to use the W2G drive, I couldn't the needed Apps installing.
It worked once with consumer preview... thanks for the help. I will try to get the "real thing" from Kingston. I see it as a replacement to allowing user to connect from their own PC to the corporate network.