2005 A6, anyone have any ideas where and why this might be leaking and how to fix? Thanks

 

I have the same problem in my 90 quattro 20v.

Would like to know why also.

Thanks for all help.

 

Take the lamp out, take the bulb assambly off, keep it in the house or garage untill it dries...or blow it with a hair drier.
Put the bulb assambly back on and inspect the seal. Most likely the last time a bulb was changed, or when they put it together at the factory, they crossed the gasket or something.
If you see that there are gaps, even very litle, use some gasket maker from Canadian Tire. Silicone works too, but you want something that will not glue there permanently. Will adhere to the surfaces but is soft and rubbery enough to break next time you need to change a bulb.
Put the lamp back and enjoy