usually authentication problem occurs in email only bcoz of two reasons...either when the password you are entering is incorrect or the email adress is incorrect. Now m sure you must b entering correct email address. Just make sure you are entering the right password. If the password you are entering you think is right. Try to reset it by contactibg virgin media technical support (TSC). Once a chap out there will reset your password, you can try to enter that in your email client ( iphone, android, outlook, windows live)....also by going into server settings you must make sure that the incoming server of your email is "pop3.ntlworld.com" or pop3.virginmedia.com" and the port number is "995" similarly the outgoiing server is "smtp.virginmedia.com" or "smtp.ntlworld.com" and port number is 465. This will help you in overcoming the problem of unsent emails.
- I work for Virgin Media, but opinions are my own.
I believe the full error is 500 Authentication denied (VM 311).
It's actually not down to an incorrect password which is 535 Authentication Credentials Invalid (VM 300).
Rather this is down to an anti hack feature on Virgin's system that doesn't play nicely with Gmail's outgoing SMTP.
Essentially when you send an email via a third party address Gmail's outgoing SMTP server connects to Virgin's outbound relays in the same way your standard SMTP client does. HOWEVER the connection can come from one of several different IP addresses as Gmail have several outbound servers.
If several messages are sent within a short space of time, VM's system counts the different IP's used to authenticate and if it reaches a certain threshold, locks out any further authentication attempts for a time, with this message.
@Nicola_C - Has explained this before now so I'm not breaking any confidences by posting this. Nicola, would you mind taking a look at this and speaking with the Email Team?
Only use Helpful answer if your problems been solved.
Thanks for your reply, that seems to make sense to me, as I am travelling at the moment and have no wifi, so when I get to my hotel and pick up the wifi on my phone and iPad, I am sending various replies from both devices all at once.
i could not send last night, but now today it seems ok, but I didn't get many emails today.