Hello to everyone!

I have just bought Nokia N900, so I could play with Maemo and do some other stuff with this lovely phone, but not sure about something...

I think it is Symbian installed on this phone, and not Maemo, is this possible? Or maybe some other os, no way to check that on the phone itself?

I have tried to flash it with the latest Maemo firmware and emmc, but when I connect the phone to my PC, while holding the U key, nothing happens, I just get that battery charging animation on the Nokia N900 screen, so no NOKIA logo, no USB icon etc..

I have lost days searching for info on how to do this and I really hope someone here can please help me out with this, so I don't go mad and jump out the window?

How ffs do I install Maemo on this beautiful piece of tech, please, someone, anyone?

Thank you!

p.s. Yes, I have tried to flash, exactly as per instructions, on Windows 7 32 and 64bit, Windows XP (including service pack 2, and 3), Windows 10, OS X El Capitan and Linux Debian. Always the same, all os-es detect N900 as a mass storage USB device, not a phone.