ERROR: none message must be encrypted

[fuzion1]

We have an IPsec setup with pfsense and a sonicwall.  It is becoming very unreliable, and disconnecting completely almost every night.  To fix it I have to go into pfsense and reset the connection.  I think all of this is caused by the error I am getting in my pfsense log.  It repeats this error a couple of times a second.

Oct 7 08:38:53 racoon: [Nashville]: [] ERROR: none message must be encrypted
Oct 7 08:38:55 racoon: [Nashville]: [] ERROR: none message must be encrypted
Oct 7 08:38:58 racoon: [Nashville]: [] ERROR: none message must be encrypted
Oct 7 08:39:00 racoon: [Nashville]: [] ERROR: none message must be encrypted

Does anyone know what I can try to fix this issue?

[jimp]

That means the sonicwall is trying to send you data without encrypting it, or it's sending data on a connection that pfSense no longer considers valid.

Check these:
https://doc.pfsense.org/index.php/IPsec_Troubleshooting#Renegotiation_Errors

[adam65535]

Just want to add that this can also mean the shared secret does not match.  I just ran into this error recently.  The remote end (Checkpoint) revealed in the logs that it could be a shared secret mismatch.  Sure enough it was off on one character.  The pfsense side was initiating the connection.