Firewall stop showing logs neither through CLI nor GUI (601E)
Helo everyone,
Since yesterday, I cant see any log on the Fortigate (On friday, 3-4 days ago, it was working). I tryed through CLI and GUI. When I tryed in the web interface, the firewall starts searching for logs but it shows:

The severity of the logs is set as Information:
config log memory filter
set severity information
set forward-traffic enable
set local-traffic enable
set multicast-traffic enable
set sniffer-traffic enable
set anomaly enable
set voip enable
set filter ''
set filter-type include
end
I read that maybe reformatting the flash disk it get solved, but I would like to confirm it and know if someone suffered this problem before.
The firewall is an Fortigate 601E with v6.4.8 firmware version.
I hope someone could give some advice.
Thank you in advance!

