Well, I disabled AJAX support in HOST SETTINGS and restarted the application and then had my end-user try to work on his site.  He still gets the error.  A little explanation of what he has set up:  He is using the WIKI module that came with DNN and he has at least 3 levels built.  The problem occurs when he tries to edit anything below level 2 (IE the head node points to then next level (2) which has pointers to their next levels (3).  I hope I am making sense.  But now he is saying that he was able to add a new node at level 3 and edit its content.  It is looking like the old nodes at level 3 just aren't editable for some reason.  He is going to try to recreate all of the nodes at level 3 to see if at some point the problem was fixed and the old nodes are simply corrupt or something.

Also, please try yourself. we don't know how is your user's browser configuration.

Ven:  That must have been it.  Everything going forward seem to be working at this point.

Mauricio:  I am not sure if it is limited to the Wiki.  It has only been expereinced there, but this particular end-user is more active with hi Wiki and any other end-user any of the other modules.  Also, I do not believe it had anything to do with the browser, other than IE, as mulitple versions of IE were experiencing the problem.  And I did try it for myself, following this end-users direction down to experience the problem first hand.

At this point I am going to say our issue is resolved.  Thanks everyone!