Invalid duration specification with FFMPEG - what could be the reason?

Using a command like:

ffmpeg -i input.mp4 -c copy -t 00.11.10 -map 0 output.mp4

I get:

Invalid duration specification for t: 00.11.10

Similar error for -to and -ss.

What could be the reason for that?

Answer

Your duration format is the problem, you have used dot (.) instead of colon (:).

Duration may be a number in seconds, or in hh:mm:ss[.xxx] form.

Try -t 670 or -t 00:11:10 instead.