Hi,
This error appears only when you have source WordPress installed in a sub-directory and you are trying to create a staging instance into another sub-directory within another sub directory.
If you have the installation in the root of your domain this error should not appear. If you can open a support ticket with us we can check this for you :
https://softaculous.deskuss.com/
We have also fixed the cannot typo and it will be updated in the next version of Softaculous.
(ignore my previous post)
Actually, your note about subdirectories got me to recheck the installations, and I found something interesting :
My site is installed in the root of the domain : https://www.domain.com I wanted to create a staging in https://www.domain.com/_staging Then I get the error
(this is my old temp domainname) it works, and I also can do a push to live on www.domain.com
Original WP installation on https://www.domain.com was done in /home/myaccount/domains/domain.com/private_html
(I don't know why, because I did do the necessary to create the symlink from private_html to public_html)
but I can see that when trying to create the staging under a different domain, it always tries (correctly) under /public_html/ /home/myaccount/domains/domain.eu/public_html/_staging
Which lets me believe that when trying to create the staging in https://www.domain.com/_staging, Softaculous is also trying to create the staging in /home/myaccount/domains/domain.com/public_html/_staging?
So before opening a support ticket, I will try to fix/move the original installation into /public_html