I executed the following command, and I got an error message.
unison /run/media/Erick/4E8CA1738CA1566D/Best_VDO /run/media/Erick/My Book/1.0 TB Volume/Best_VDO
Usage: unison [options]
or unison root1 root2 [options]
or unison profilename [options]
For a list of options, type "unison -help".
For a tutorial on basic usage, type "unison -doc tutorial".
For other documentation, type "unison -doc topics".
unison was invoked incorrectly (too many roots)
Can you help? I think it has to do with how I mounted the two disks, but I do not know exactly why.