So, I’ve reduced it to the bare bones - two files containing only a single IBM line-drawing character (0xC4). File 1 is a 9-byte file with 9 consecutive instances of this character and opens fine, file 2 is a 10-byte file with 10 instances of the same character and won’t open.

Adding CRLF or EOF at the end makes no difference. Moreover, saving a file which has opened blank results in a zero-byte saved file.

I’ve countless other files which contain various line-drawing characters and some of them display properly, others as squares but they always save correctly, it’s just these few files that simply won’t open in npp (they open, but nothing is displayed).

Any thoughts??