Thanks for responding Matthias,

I was referring to this forum (dotnetnuke.com). On the "My Settings" page it allows for notifications or Tracking Forum (which at one point about a 8 months ago did word beautifully) of all forums or sub topics. If I select to receive notification (on my settings page), select update, then return to the page, the "Receive Notifications" checkbox is mysteriously unchecked. I have not been able to receive notifications (Tracking Forum) in at least 8-9 months.

Please advise.

Please try I.E as your Browser if you use a other like Firefox, Opera as so on.

I am a little confusing about that this issue is caused to you. 

I only think there was any thning wrong by doing the upgrade/install  the Forum.  i.e :  Some permission issues on the physical pats and folders, and or some missing permission in the IIS.

So as example if the IIS setting to execute scripts only, only the SqlDataProvider are upgraded, not the Module files.  This must be set to the scripts and Executables. Also must the annonymous User (IUSER_xxx) have read permissions for all files and folders.  So I think perhaps the database was upgreated but not the forum files. 

The best way I think you can find out is to make a seperate instance of DNN with the Forum Module to check your production side.  Check then all spocs, vies and function. Before doing this check please your permission settings in the IIS and for the physical paths and folders.