That's a filesystem issue you can almost always recover from that by manually running fsck several times:
Running a file system consistency check on the SG1100:
At the SG1100 console press any key to interrupt the boot loader when you see:
Hit [Enter] to boot immediately, or any other key for command prompt.
At the prompt enter: boot -s
That will boot in single user mode to a question asking for a path to the shell, just press return to reach the # prompt.
At the # prompt run the following command: fsck -y /
Run the fsck command at least 3 times; Repeat the command until no errors are reported, even if fsck claims the filesystem has been marked "clean".
Reboot by running: reboot
It should boot normally and with no residual long-term issues.
But if you do need the recovery image please open a ticket with us at https://go.netgate.com and we'll come straight back to you with that.
Steve