Proofing Language Changes do Not Take Effect

[Andrew H]

Upon discovering that my spellchecker was operating in French I did Review -> Language -> Set Proofing Language and changed to English (US). I also unchecked "Detect Language Automatically". No love. I confirmed that the setting had indeed been changed by re-doing the Review -> Language -> Set Proofing Language sequence and noting that English (US) was indeed what had been selected.