I don't know how you have deleted the files and folders.
Normally, you would have deleted Symbolic Links and not the master files and
folders.
As you did it manually, I don't know where you go in the directory and what
you have done.
I don't know which tool you have used.
Did you use a SSH terminal or a FTP tool or something else.
The delete of the original directory may be resulting of the tool you have
used to delete the directory.
I don't know if your "back-end" problem occurs on your master website or in
the slave site.
When you say that you reach the "front-end", which one.
Are you redirected on the master "front-end" when you try to login in the
slave site back-end.
If this is the case, perhaps that the slave site is not defined.
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