@hokaido the log can be found in the current users their my documents folder as yyyyMMdd_nextcloud_outlook.
That does sound like a really strange bug. So if I understand correctly selecting multiple files doesn’t work, however when you use the file picker and select files one-by-one (open close etc) and you upload then it does work? Or you need to upload all those files individually by upload files, pick file, upload, repeat? I am curious with the log results.