[ovirt-users] Can't add disks at all

Hi guys, I've got a strange one. I'm running ovirt 3.5.x with NFS storage from two NAS's All my VM's are running fine, however if I try to add a new disk, I click OK and nothing happens. Nothing is logged in the ovirt logs or the vdsm logs either. I've tried different browsers, I've tried tried changing the disk type etc, but no matter what, I click the OK button to add the disk, and the button shows it's been clicked, but the page just sits there, eventually after waiting 5-10 minutes I have to click cancel. Nothing is logged under tasks, etc in the ovirt GUI too. I have tried restarting my ovirt engine completely. My engine logging is working as I do see logs when I click around in my ovirt GUI. One of my storage domains is 100% full(400MB free), and I get a warning about this in the event logs, however the domain I'm trying to add it from isn't the full one. Any ideas where I can start looking? Thank you. Regards. Neil Wilson.