I am suddenly experiencing the above error which, from previous threads, needs to be reported here in order to be logged and fixed. Unless there is any other advice! Everything was working fine and suddenly I can't send a thing although I receive emails fine. All my settings are correct. Thank you!
Oh dear! You have done well to get the error code, now the hard work begins. A lot of it has to be done by you or a trusted assistant in your home using your broadband, as your IP address is likely blocked due to spambots and malware. Read this thread and come back if you need help - we will help, but need you to start it off and tell us more and where you are getting stuck or have queries.
In the meantime, you should be able to send emails using VM webmail on an internet browser, which is allowed even though your IP is blocked for other purposes. Or a mobile device using data (i.e. not connected to your IP address).
Thank you. This pointed me in the right direction, and I had been blocklisted. I had to use a tech support company in the end as it was getting a bit challenging for me. All seems resolved now so thanks for your help!