Nikon D6 Reference Manual page 1069

Error Messages
The following alerts appear in the monitor and top control
panel:
Alert
Monitor
No memory
card.
Cannot access
this memory
card.
Insert another
card.
Top
control
panel
Memory card not inserted or inserted
S
incorrectly.
Check that card is inserted correctly.
Error accessing memory card.
•
Check that camera supports memory card.
•
If error persists after card has been
repeatedly ejected and reinserted, card
may be damaged. Contact retailer or
Nikon-authorized service representative.
W ,
R
Unable to create new folder.
(flashes)
•
Delete pictures from memory card until
there is room for additional pictures to be
recorded. Copy pictures you wish to keep
to computer or other device before
proceeding.
•
Insert new memory card.
Problem/solution
Alerts and Error Messages
1017