Here's my macro for flashing;

[0007NoFlash]As best as I can tell, the flashing is missing between deck and house. Flashing is meant to protect wood from moisture damage/deterioration. I am unable to determine if damage is currently present. I do recommend you contact a qualified carpenter to obtain accurate cost estimate to install the proper flashing. When flashing is being installed, it can then be determine if moisture or other damage does exist.

Darren
New Jersey Home Inspection - About the House!