Upload mission does not work

uploading a mission does not work anymore.
Has anybody a workaround ?
I have tested AP 3.6.7 also.

Mission Planner for Ardupilot 4.0.0 (aka Tower)
ArduCopter 4.0.3

I don’t use Tower anymore but I have it on an old Android phone and it uploads fine.

which ArduPilot version are you using ?
Are you using Tower or Mission Planner for Ardupilot ?

changed to Skydroid Tower app.
Mission upload works.

Latest Dev version of Copter and Tower.