I have this problem too...
CODE
Directory listing successful
Status: Creating directory '/forum'...
Command: MKD forum
Response: 550-Can't create directory: Read-only file system
Response: 550 0 Kbytes used (0%) - authorized: 6144000 Kb
Command: MKD /forum
Response: 550-Can't create directory: Read-only file system
Response: 550 0 Kbytes used (0%) - authorized: 6144000 Kb
I'm using the most up-to-date version of FileZilla.
I am quite confused :/