Forum Discussion
UK english
Maybe the issue here is that UK English is more likely to accept spelling alternatives (I am not sure). Of course, allowing for spelling alternatives is not going to be helpful for anyone who wants to ensure consistency.
As Charles said, language formatting is unnecessarily complex in Word—or at least it isn't fully transparent.
To verify that the language is correct in the document, select a small portion of text, such as a single word, and then visit the Language dialog box (Review tab > Language group > Language > Set Proofing Language). Repeat this with other words in the document.
This is necessary because Word may not correctly display the language if you select a large portion, such as the whole document.
However, it is possible to re-apply the correct language to a large selection, such as a whole document. That is why re-applying UK English should work (and that is why Charles suggested doing this). In such an instance, you just use OK in the Language dialog box (do not choose Set as Default because you are not changing the default).