you need more space, that's for sure. Depending on where your FSDB is located, you can either move away files that doesn't belong to the FSDB, or you can stop the service, go to disk management are extend the partition, or you can move your FSDB to different drive, or to different server in your network - see SolarWinds Knowledge Base :: Changing the NTA Flow Storage Database Location. Once there will be enough space again, migration will continue. Make sure to allocate some extra space for future, as the DB usually grows about 5x bigger it was right after migration during next 30 days.
