InvalidCastException when opening root-level Navigation settings page

Question

I couldn't find any information about this error anywhere and it's really strange!

When I open the root-level Navigation settings page in my SharePoint 2010 website, I get an error page and the following message can be found in the Event Viewer: Exception type: InvalidCastException Exception message: Unable to cast object of type 'Microsoft.SharePoint.Publishing.CachedListItem' to type 'Microsoft.SharePoint.Publishing.CachedPage'.

I've tried clearing all of the SharePoint 2010 related caches but that didn't work. I also haven't modified any part of the root level navigation in a long time. I think the last time I opened the page was a month ago or so!

Any ideas?

The master page I'm using is is v4.master.

Cheers guys!

Answer 1

Alright so this turned out to be a really random problem!

So I started developing this site on one server, then our server infrastructure got updated so I backed up the site collection and moved it to the new server. I had left the /Pages/default.aspx checked out and when I tried to view the /Pages library in the new server it was always empty. When I tried to create default.aspx manually SharePoint always gave me an error so I decided to rename the old Pages library to Pages2 and then create a new Pages library manually. When I then copied my default.aspx page to the new library everything worked EXCEPT that when I open the root level Site Settings -> Look and Feel -> Navigation I get the InvalidCastException error.

So when I delete my manually created Pages library and rename the old Pages2 library to Pages the navigation settings page doesn't give me an error anymore! Now I will have to delete the default.aspx that SharePoint tries to hide from me using PowerShell I guess..

Hopefully this helps someone else!