Can’t force stems down


I try to force the stems down for the first four notes in this example:
Bildschirmfoto 2016-11-28 um 10.00.34.png
How is it possible, as the „Force Stem Down“ from the Menu does not work?

I had this problem once or twice, and — strangely enough — choosing “Remove forced stem” did the trick.

Thank you Marc,

this helped me, too.