not happening with any stock skins. Also, i added outlook and word to excluded list and does not prevent the issue from happening even after restarting the machine.
If you install any skin that has a dark Explorer background forget any Microsoft office product. When making a WB if the maker makes the Explorer what ever color it will always control Microsoft.
I use Office often and no matter how dark I may make a WB I don't make the Explorer BG that dark.
You change that image and or color lighter you can have the rest of the skin dark except for the Explorer BG and use Office. Note Win 10 you want to go into SKS/ Change skin colors/show me the skin defined system colors. Make where it says "Explorer background (Win 10) and Explorer folder bar background (win 10)