FTP usually shows the complete path of where the SMF files are located on the server. This path may be used in many places within the administration panel. There are differences from one host to another though, so you need to ask your host to provide you with this information.

Some examples of SMF directory and FTP 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