Since some months our app aborts printing via bluetooth on a DPP-250 printer in the middle of the text. I wrote a minimal app to test this (see attached zip). The jpg shows some tests: The first works, the next two abort, the next works, the last aborts. I'm using B4A 8.50 with Serial 1.26. The tablet is a samsung Tab A (SM-T585) with Android 8.1.0. The App simply opens the Serial, initializes a TextWriter with its OutputStream, prints some lines, closes the TextWriter and disconnects the serial connection. This should simply print the lines. But sometimes it doesn't print the whole text, but aborts in the middle of the transmission. Since I have no possibility to check if all lines are transmitted before I close, I don't see what I could do to fix this.