Case (maybe) closed - thank you and bye, bye.
Ok, for people who are really interested :sign0008::
Started coding again finally and at one moment saw a fast disappearing message on my device that the memory was low (using Bridge, fyi).
In a previous post I mentioned that almost all of my apps suddenly were moved to the internal memory (still no idea what caused this).
Moved most of the apps back to SD (more than enough space left).
Then I also remembered that "Can install to external storage" was unchecked.
Strange thing as well, because it was always checked.
Checked it again and ran the code.
The original error appeared "Application not installed".
Luckely I had another Micro-SDcard, put that in the phone, ran the code and everything went well, pfffffffffffffffff.
So, I wonder why/if the Micro-card did not live healty very long (5 months) and I don't understand why I can move apps from internal to external storage but B4A Bridge or B4A Designer don't like the iny tiny Micro-card.
Suggestions and ideas are always more than welcome.
Greetz,
Helen.