Microsoft Custom Translator: "The document '._..._...txt' is not a valid text file as it contains one or more invalid characters"

Question

When using the zip file format to combine two parallel files, after data file upload we get the error message:

The document '._{name}_{lang}.txt' is not a valid {type} file as it contains one or more invalid characters.

Answer 1

The issue is that MacOS includes system files in the ZIP archive, and Microsoft tries to read them as data files because of the language suffix and .txt extension.

unzip -l data1.zip

Archive:  data1.zip
  Length      Date    Time    Name
---------  ---------- -----   ----
        0  04-09-2020 00:57   data1/
108746839  04-08-2020 23:55   data1/data_en.txt
      120  04-08-2020 23:55   __MACOSX/data1/._data_en.txt
126795036  04-08-2020 23:56   data1/data_de.txt
      120  04-08-2020 23:56   __MACOSX/data1/._data_de.txt
---------                     -------
235542115                     5 files

The fix is to compress them in a way that they are not added, or just remove them:

zip -d data1.zip __MACOSX*
zip -d data1.zip __DS_Store*

See https://apple.stackexchange.com/questions/239578/compress-without-ds-store-and-macosx, Mac zip compress without __MACOSX folder?...

Thanks to @ScottG for debugging.