Perhaps that is a clue. The meaning of 'OEM' is obvious, the initial letter 'C' may well signify 'Client' (as opposed to 'Server') which is 'MS-speak' for the workstation install media. I deduce that from another W7 ISO that has '_CLIENT_HOMEPREMIUM_' in its name. My Computers. Laptop Toshiba Satellite L750 10 Home x64 (22H2) (10 Pro on 2nd pc ... More @Wikipedia
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