Our company uses QNAPs for our client backups, and I've had at least 3 have the same problem when they fill up.
Pull the drives, reset the unit. Restore defaults and plug the drives in when it asks you to setup the drives. DO NOT INITIALIZE THE DRIVES. Ignore the message about the data being erased before it starts to do its setup. Once the unit is back up it should show the volumes and you should be able to delete the files.
Have you tried sshing into it? Last time I used a QNAP this worked OK, and if you can get in through ssh you should be able to free up some space.
If that doesn't work, and you don't mind voiding a warranty, you could pull the thing open and move the system disk into another machine, mount it there, and clear up free space. I haven't done this, so I don't know if there is a disk you can relocate or not.
Our company uses QNAPs for our client backups, and I've had at least 3 have the same problem when they fill up.
Pull the drives, reset the unit. Restore defaults and plug the drives in when it asks you to setup the drives. DO NOT INITIALIZE THE DRIVES. Ignore the message about the data being erased before it starts to do its setup. Once the unit is back up it should show the volumes and you should be able to delete the files.
Have you tried sshing into it? Last time I used a QNAP this worked OK, and if you can get in through ssh you should be able to free up some space.
If that doesn't work, and you don't mind voiding a warranty, you could pull the thing open and move the system disk into another machine, mount it there, and clear up free space. I haven't done this, so I don't know if there is a disk you can relocate or not.