I have a 2008 E220 Avantgarde, I have a just had a C service carried out but my local garage said I now have to go to a Main dealer to have the message removed.
Is that true or can (or they) do it?
I will give it a go myself if someone could explain how to do it.
Thanks in anticipation of a positive answer.

 

Try this (taken from another site):

1 turn key to #2 position
2 go to mph display in the cluster
3 turn key to off position
4 turn key in # 1 position
5 press trip odometer **** three times (QUICK) voltage will appear on display
6 select Down Arrow (shows service menu)
7 select confirmation using -
8 Press the right menu systems button
9 full service will be highlighted
10 Press and hold right menu system button until service confirmed message appears

 

Many thanks, will give it a go.