I have been using my mobile SD with Windows 8 quite happily until yesterday evening. I successfully upgraded my Sky Demon Plan to 2.6.0 but when I attempted a sync, the sync failed with the message "GUID should contain 32 digits with 4 dashes". I used my computer to open a file called debug.txt and the relevant part is reproduced below. The problem is that my Mobile SD is now completely dead. It boots as far as the terms and conditions screen and then falls back to the GPS/Media/Bluetooth etc. screen. I have used the contact form to ask SkyDemon for their opinion and they have not had time to reply as yet, so if Sky Demon is reading this, be aware that this is a duplicate request for help. These things always happen at weekends!