Do you mean you can't get email working in general, or email works but you don't get attachments with the message?
Anyway, here is how I got Gmail working:
- Set DNS to 8.8.8.8 and 8.8.4.4
- Enable SSL in email settings
- Use smtp.gmail.com on port 465
- Turn on Google's "allow less secure logins" setting
That did it for me, and I repeated the process easily when helping my neighbors set up their LTN8708-P8.
I did have one Gmail problem which I didn't see mentioned around here... I thought this was interesting. I'll throw out the problem and solution just in case it helps someone.
Since you need to reduce account security to use Gmail with the NVR, I decided NOT to do that to my main account, but to make a new account JUST for the NVR to use when sending email. Hey, accounts are free!
This worked fine, UNTIL I added my phone number to the new NVR account. It's the same backup phone number that my main account uses. I forget the context, but I saw something in the account settings that make it clear Gmail knew that my NVR's "burner" account was associated with my main account because they shared a phone number. And right when I saw that, NVR email began to fail.
I can't be sure, but I suspect that since Google knew that the NVR email was associated with my main account, the more strict security settings on my main email silently took precedence.
Then I tried making a second Gmail account for the NVR. This time I used my home phone to verify the account--a number I had never tied to any Google service before. This second email account worked fine with the NVR.
I may be reaching here, but based on what I saw: if you are a Gmail user, make a new reduced security Gmail account for your NVR--and do not use the same backup phone or email that you use for your main Gmail account.