To do this you will need to add a bit code. I have just tested it, and it appears to work if you test the file here: https://validator.w3.org/i18n-checker/check#validate-by-upload+
The way to do this is to add a tJava to the beginning of your flow (before the file output component). Then add this code (or a variant of this code) to the tJava.....
String filename = "/Users/richardhall/Downloads/test.CSV";
String content="";
byte[] bytes = content.getBytes();
try (OutputStream out = new FileOutputStream(filename)) {
// write a byte sequence
out.write(0xEF);
out.write(0xBB);
out.write(0xBF);
out.close();
} catch (IOException e) {
e.printStackTrace();
}
You will also need to add these imports to the tJava's advanced settings...
import java.io.FileOutputStream;
import java.io.OutputStream;
What this does is create the file and adds 3 BOM bytes to the beginning of the file. The only change you need to make to the file output component is to set the file to Append and to not fail if the file already exists.
