sftp backup permission error

When setting up the backup to a remote location, I get this error:
"
Error: Validation for transport “c1” failed: Could not upload test
file: Couldn't open remote file '/validate.tmp-27690-1501312901.txt':
Permission denied
"

It is very strange that cpanel does not include a proper hint/explanation/example exactly where this is needed (in the backup setup underneath the heading but before the input field of the backup path), since leaving it with the default "/" yields a permission error (which is hard to figure out and the quoted post above was the only hint available, as cpanel help does not explain it). Insufficient care and testing is again the reason for this. And it is over a year...perhaps get some interns to test?

(side note: The whole design of that backup setup is not very clear
and it is not straight forward either re which keys, etc. I suggest
you test a lot more with people who are not whm/cpanel experts and
who've no time, b/c such constraints reveal better what's needed.)

 

When trying the first time, the field contained "/" and brought up the quoted error message. Then later "/yourdirectory" was tried, with the same result. Only after reading the previously quoted post by @kiti was "yourdirectory/" tried and worked.
Both ftp servers are pure-ftp on two same version WHM/cPanel.

However, to my surprise, when setting this up today again, neither empty field nor plain name without forward slashes (front or back) brought up any error!?! Also, when the plain directory name was used with a digit at the end "yourdirectory2" it ignored it and used "yourdirectory" only?!?

No clue how this is possible, but maybe (there is more intel in it and) 'it found' old backups there and 'thought' it was 'the right' directory

Thanks for looking into it!

 

Very kind of you, it works now, so no need to waste resources.
(And the digit at the end was in the name, not the directory, as I found later (must have been tired 4am), so this is not a surprise/bug, but mea culpa spotting a non-error/false alarm. But the other stuff happened that way.)
Thx