Question : filezilla "could not start transfer"

I'm trying to backup my server, but for some files I get "could not start transfer".

I suspect it might be a permissions problem.

Answer : filezilla "could not start transfer"

Likely it is permission problem where you don'thave read permission for that file.
Check out if the user account that you login and start the backup have read permission for the file. You will also have to have the read permission for the parent directory before you can get that file.