Well the syntax looks correct.
Although the width is extremely large for a side island.
Not knowing what forum you used it in.
Can you provide a url link to the forum it should appear in?
Does a ad show at all?
Did you select the island in custom inserts for the forum?
Did you enable viewing ads in the forum permissions also?

FYI,
I do see a google search ad island in most of the forums.

Last edited by Ruben; 02/11/2015 5:48 PM. Reason: Added Comment

Blue Man Group
There is no such thing as stupid questions. Just stupid answers