downloading file using scp command

Just add where you want it to be copied to (ie: ./):

scp [email protected]:/root/pcfilename.rar ./

First of all, make sure that the root user is really needed to access the file. If the file can be retrieved by a normal user, that would be preferred to limit the security risks.

If root is really required, make sure that root is actually allowed to login by ssh by checking your /etc/ssh/sshd_config file and see if the PermitRootLogin option is set to yes.

Finally, your command above should work when you add a . (pointing to your current dir) behind it, like so:

scp [email protected]:/root/pcfilename.rar .

Or you can always use a full path as well:

scp [email protected]:/root/pcfilename.rar /home/user/pcfilename.rar