MkIII Update with V28 - MkIII doesn`t work now

[Thorsten]

HI,

I have a problem with a MkIII nav system.
I have insert the V28 firmware CD for the latest MkIII firmware.
The dispaly writes the message update CD insert, then gets the screen black. I waited for the update screen, but the screen was black.

Then, I turn off the ignition, wait a few minutes, turn on the iginition.
The screen work, but I have only the points radio and cd changer, no nav function is available.
The firmware cd is in the navsystem, I can`t get out the firmware cd.

What could be the problem?
Has I damaged the nav system?