Are you running a language pack with AutoCAD Electrical, or just plain english?
There is a known problem when you have a language pack installed. The manufacturers are added to the default_cat.mdb located in My Documents\Acade 201X\aedata\en-US\Catalogs
Copy these files to YOUR language folder.
Trond Hasse LieEPLAN Expert and ex-AutoCAD Electrical user.
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