flashing unbranded OS on Lumia 800

[holzlondon]

I've just upgraded to a new phone from my old Lumia 800. Now, it has the branded T-Mobile (Germany) software on it. As far as I know, it isn't SIM-locked though.

I'm getting the phone ready to give to my aunt, who is quite excited about her first smartphone (how sweet...) I'd like to give her a totally unbranded phone, but I'm not sure if it's easy to flash an unbranded software on the device.

Can anyone advise me? Thanks in advance!

 

[lordsnow]

Almost all Lumia 800 came with locked bootloader, so it is impossible to flash another ROM :/