The FTP local path to SMF is a directory path required by the package manager to set file permissions. It differs widely from one host to another, so you need to ask your host to provide you with this information.

Some examples of SMF directory (server settings) and FTP local path to SMF:

Control Panel	Server Settings SMF directory	FTP server	FTP Local path to SMF
Plesk (in forum subdirectory of domain)	/home/vhosts/domain.com/httpdocs/forum	domain.com	httpdocs/forum
Plesk (in main directory of subdomain sdn)	/home/vhosts/domain.com/subdomains/sdn/httpdocs sdn.domain.com	httpdocs
cPanel (in forum subdirectory of domain)	/home/<username>/public_html/forum	domain.com	public_html/forum
cPanel (in main directory of subdomain sdn)	/home/<username>/public_html/sdn	sdn.domain.com	public_html/sdn