I tried to reset my Folio to stock from Foliostock.zip and flashed the Open Recovery/recovery.img via fastboot (fastboot flash recovery recovery.img) and erased everything cache, system, linux, userdata ("fastboot erase cache" and so on). Then put update.zip to sdcard and installed from original recovery. But every time I tried to boot to Android I got "Magic value mismatch". Tried everything, factory reset etc but nothing worked. Then did these steps and the stock works again.
3. fastboot -w
4. fastboot erase linux
5. fastboot erase system
6. fastboot flash system dexter-root.img (from Foliostock.zip or update.zip/cache/)
7. fastboot flash linux boot.img (from Foliostock.zip or update.zip/Open Recovery/)
8. fastboot reboot