Log browse error --- missing FMT message

I got the attached error message when trying to browse a BIN file after downloading.

How do I get the FMT message in my log ?

Appreciate your help.

You got this message because the file you tried to open, is either not an ardupilot binary log file or corrupted. Try to open it at plot.ardupilot.org to check it.

Thank you. Will try.