Fixing the PowerPoint Proofing Language in Master
Fixing the PowerPoint Proofing Language should also change the settings for the Master to avoid introduction of wrong proofing language.
We’ve investigated this and recommend to use the SlideProof > Text > “Set Proofing language” feature as a work-around. This will change all shapes in the Slide Master as well. For now we didn’t include this into the Check feature as it will have side effects (showing warnings about the master, when on the slides everything is fine).
Also another situation where wrong proofing language is re-introduced is when the editor has the wrong input language/keyboard layout selected in Windows. This sometimes trips PowerPoint.