AuthenticationInvalidCredentials: 5.7.0 Denied

[Moez Tharani]

Hoping for some help here. We are getting this error after activating our maintenance license when trying to test the 3cx email server. We've followed some steps we saw here, including re-saving the license, restarting server, etc. This has been ongoing now for 2 weeks. The company we purchased the maintenance license through has been no help, only saying that they are investigating internally. We need to get this fixed right away!

AuthenticationInvalidCredentials: 5.7.0 Denied

 

[cobaltit]

I've seen this happen when a firewall configuration is screwed up. If the static IP defined in 3CX doesn't match the IP the 3CX SMTP traffic comes from it will be rejected. I'd try switching your system from static to dynamic, restarting and testing. This is assuming you are on the latest update (Update 6) and you are currently setup with a static IP in 3CX.

PS. If this fixes it you should consider renewing your license from someone else, like me

 

[YiannisH_3CX]

Hello @Moez Tharani

As @cobaltit mentioned this error usually means that the IP your server activates from does not match the IP the email requests are coming from. The setting your IP to Dynamic and restart all services. Then try re-activating the licence before testing the SMTP again. If you have multiple public IPs make sure that traffic goes out from the same IP.