I have read the posts about the multilevelSectionMenu that were posted here before, but nobody has really found a solution....

I am encountering this error also. 

I decided to do some debugging.

What I noticed:
   1.  When a user is not logged in, The MultiLevelSectionMenu is always passing 0 as the _sectionMenuLink.SectionID
   2.  When a user is logged in, the _sectionMenuLink.SectionID is getting set as it should be.

Why would this be happening?

Thanks,

Keith Willis

I have found out why this is happening....

I have included 3 menus on my page.  I have one that is going across the top, one going across the bottom, and then the multi-level menu.

The problem is I am mixing the types of menus that I want to appear. 

In my case, the first menu to load was the top one that doesn't have multi-levels.  This item was not loading the submenu items.  Well, when this loads, it puts the items in the cache.  The same cache that the multi-level pulls from.

When I modified this to pull from different cache locations, there were no more problems.

Thanks,

Keith