Probably a samba problem:
http://unix.stackexchange.com/questions/10736/samba-reporting-not-enough-free...
http://www.linuxquestions.org/questions/linux-server-73/samba-share-reporting...

Depends on what is your share path in smb.conf for your samba share. is it /tmp or /tmp/.cemnt (both of which are ~126MB on a pinky)? Instead of /tmp/.cemnt/mnt_sda1? or whatever you data transfer drive is mounted to.

Ok bubajoe, I remember you now, you used http://www.ctrlaltdeleted.com/?p=3 to modify your plug http://www.pogoplugged.com/forum/thread/16257/unable-to-edit-smb.conf-file/ . So the size that is being reported is for /tmp/.cemnt where if you do "df -h" is probably 124 MB free. So if you had a 2 TB drive attached ot /tmp/.cemnt/mnt_sdb1 or whatever, because your share path is at /tmp instead of the drive itself, it will always report 124 MB until you fill up your 2 TB drive with files less than 124 MB each and then it will be less than 124 MB. So to have it report the actual size of the drive, then change the share path in your smb file to the actual drive itself.

Edit:
Type "df -h", you'll figure it out.

This is just an example of your system, use it at your own risk, no warranty implied:

[ShareA]
comment = Share A drive
path = /tmp/.cemnt/mnt_sda1
available = yes
public = yes
writable = yes
printable = no
create mask = 0777
guest ok = yes
browseable = yes

[ShareB]
comment = Share B drive
path = /tmp/.cemnt/mnt_sdb1
available = yes
public = yes
writable = yes
printable = no
create mask = 0777
guest ok = yes
browseable = yes

[ShareC]
comment = Share C drive
path = /tmp/.cemnt/mnt_sdc1
available = yes
public = yes
writable = yes
printable = no
create mask = 0777
guest ok = yes
browseable = yes

[ShareD]
comment = Share D drive
path = /tmp/.cemnt/mnt_sdd1
available = yes
public = yes
writable = yes
printable = no
create mask = 0777
guest ok = yes
browseable = yes