Discovery Data Manager failed to open the .ncf (assignment rule) file for site "%1".%12 Possible cause: The file is corrupt. ...

%11Discovery Data Manager failed to open the .ncf (assignment rule) file for site "%1".%12

Possible cause: The file is corrupt.
Solution: See if an .ncf file exists in the directory Inboxes\Ddm.box\Data.col. If so, delete it. The site control file will recreate it. If there is no .ncf file in that directory, stop and restart Discovery Data Manager. You can use Configuration Manager Service Manager, which is invoked from the Configuration Manager Console, to stop and start components.%0