"The User Profile Service service failed the sign-in"

[admin]

I got the same error when using Win7 Pro x64 SP1. Here is how I fixed it without Windows to Go.

1. restart into safe mode with command prompt
2. enable administrator account - net user administrator /active:yes
3. reboot and login as administrator - this will error but creates an administrator folder in the users directory
4. shut down and place usb stick in another computer
5. change the ownership of the entire Users folder and Windows folder to administrator - I used Take Ownership from context menu
6. copy the contents of the default folder into the administrators folder.
7. place stick back in test computer and login as administrator.
8. Should work now.

There is obviously an owner/permissions issue when the folders are created by WinToUSB.
Hope this helps.

Please send the user.log file to us via e-mail at [email protected], the user.log file is located in the bin folder under the installation directory. 
Thanks.

problem is solved with the latest version. Thanks

No It Isn't. Problem still persists for Windows 8.1. Kindly fix the bug.

Also @dcol, can you please explain the steps involved here - 
5. change the ownership of the entire Users folder and Windows folder to administrator - I used Take Ownership from context menu
- Once you place the usb stick in another computer your domain name (machine name) changes. How do you assign the ownership to the Administrator created?
6. copy the contents of the default folder into the administrators folder.
- There was no Administrators folder. I created one and copied the contents from Default folder. It still didn't work.

A slow disk will easily cause this problem, so please try using an external hard drive, a Windows To Go Certified Drive, a SanDisk Extreme CZ80 USB 3.0 Flash Drive or a SanDisk Extreme PRO CZ88 USB 3.0 Flash Drive to create portable Windows to see if this problem stills exists.