Concurrent Mail Session Scanning

Sulcus

We're using the Anti-Spam feature in a Zywall 1100, but currently all mail traffic is being forwarded because the 'Concurrent Mail Session Limit' has reached the threshold of 1000'.

I can see the 'Concurrent Mail Session Scanning' bar is on 100%, but nothing is happening when I try to flush it.

Does anyone know how to flush the mail sessions without a reboot? And does anyone also has a clue where it's coming from? We only have a small office, and I'm pretty sure we don't have that many 'mail' traffic.

Zyxel_Charlie

Hello Sulcus,
I suggest to upgrade your device’s FW to the latest one firstly, this issue should had been fixed on this FW version.
The download link will be PM to you. 
Charlie