Would anyone be able to shed some light on why in some portals the URL contains List/0 and in others it don't?

The List/0 is having an impact on 2 of my modules, so I need a solution if there is one.

This portal started at 4.0.0 and has been upgraded along the way to now 4.3.4, not sure if this would of had an impact.

Thanks

Anthony

This is actually happening portal wide and not specifically from any module.

Some portals are aok, but around 5 of 20 portals are having the list/0 in URL. Is the list part a DNN feature of some sort? As when I fo to Host -> Lists I get the following error: You Do Not Have Permission To View The Requested File

All other host menu options are fine.

What i can notice is that when you first click on a menu item, you don't see the list/0 part in the IE status, but after about 2 seces it seems to do like a redirect and add list/0 to the URL.