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1. Install VMwareMOD EDIT Google it
2. Download firmware from this topic: for Lumia 800 , for Lumia 710
3. Download UbuntuMOD EDIT Google it.
4. Start WMvare, than choose Create A new virtual machine.
5. If it asks lock CD-ROM, say YES.
6. Go to VM>Settings>Options>Guest Isolation mark VMCI, click OK
7. Copy os-new.nb to Ubuntu's home folder.
8. Turn off your Lumia, hold pushed VOL + and POWER, plug into your USB, you will feel a short vibration. If Windows asks format USB drive, SAY NO OR IT WILL EXPLODE!