EE5G LTE Router not connecting to SMTP Email Server

[PConners]

We use a Hikvision CCTV System and since changing from Fibre (FTTP) connection to the new  4G/5G LTE EE5G router we are getting a SMTP connection error when the 'motion detect' is activated, (it send me a confirmation email with a image). - the live CCTV feed can be viewed no problem using the LTE  but I don't receive the motion detect activation email....everything works fine on standard broadband connections but the email alert  fails on 4G/5G connections, I have also tried a Netgear Orbis with 4G Fail over and get the same problem when it uses 4G (no problems using landline broadband) can anyone advise on how to help as EE technical are clueless.

[XRaySpeX]

Who is your email provider? What have you put as the Outgoing Server settings (all of them) in your Mail app, obscuring your name?

[PConners]

Hi

These are the settings on the NVR (which work fine using landline fibre connection)

SMTP Server: smtp.enta.net

SMTP Port: 25

senders address: *****@virgin.net

[XRaySpeX]

Is your landline fibre connection with CityFibre (Entanet)? If so, that's why that works.

Why are you sending from a VM email addy over a Entanet SMTP? That's a Relay & might not be allowed by Entanet.

[PConners]

This was set up originally be the installation engineer and it hasn't changed since, he used his virgin account as my Gmail do  not allow SMTP. which email provider would you suggest to change the account details too?

[XRaySpeX]

I don't get it! Seems a mix up. Why are you having your device send emails from his email addy? Don't you have an email addy of your own? 

Please answer my 1st Q of earlier. Answering all my Qs will help us understand your situation which is not at all clear.

[PConners]

no it a unused email account,  there is a forwarding (see attached) - only get the error

when using 4g LTE

[XRaySpeX]

You still haven't answered my 1st Q: Is your landline fibre connection with CityFibre (Entanet)? If not, who is it with?

What email addys do you have of your own?

[PConners]

You still haven't answered my 1st Q: Is your landline fibre connection with CityFibre (Entanet)? If not, who is it with? - Plusnet

What email addys do you have of your own? - @outlook.com  | @Gmail.com | @Me.com

[XRaySpeX]

I can't find out enough about Entanet email settings to work out why it doesn't work. Most likely it, like many other email providers, doesn't allow the SMTP on port 25 to be accessed from networks other than its own, but that doesn't explain why it works over PN.

As a 1st guess at fixing this try changing SMTP Port to 465 or 587 with SSL/TLS enabled. Try each in turn & choose the 1 that works with both the EE mobile network & over PN BB.