Navigation Menu in Sharepoint corrupt

If you get the following error:

"The page has been modified by another author on ..."

when modifying the SharePoint Site Navigation, then it is probably because of a corrupted heading node. If you find the target URL for the heading set to something like "/_layouts/viewlsts.aspx?BaseType=0?BaseType=0?BaseType=0?BaseType=0" then the heading is corrupted.

To fix the problem, you will basically have to remove them, and the header either manually, or using the list settings.

This is a known bug and allot of people have been experiencing it.

Refrences:

http://paulgalvin.spaces.live.com/Blog/cns!1CC1EDB3DAA9B8AA!202.entry?sa=199836339

http://social.technet.microsoft.com/forums/en-US/sharepointadmin/thread/0b968acf-d069-420f-bbb5-0950c81d5066/