Can’t manage public folders

When I try to set the properties for any public folder in the Exchange Manger Snap in, I get the following Error:

“The object is no longer available. Press F5 to refresh the display, then try again.

ID no: 80040e19
Exchange System Manager”

Furthermore, the virtual folders under the default web server for “Public”, “Exadmin” and “Exchange” have errors.

I tried running setup from the Exchange CD but this did no good.