Hello Internet.

So i was trying to install a new Steam folder on a removable NTFS partition and it gave me the error.
“New Steam library folder must be on a filesystem mounted with execute permissions”

The solution was to mount it like this:
sudo mount -t ntfs -o fmask=0022,dmask=0000,uid=1000,gid=1000 /dev/sdc1 /media/USER/Drive

Of course you would have to change “sdc1”, “USER”, and “Drive”

Source of solution: http://askubuntu.com/a/18053