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outgoing server may be unavailable or is refusing smtp connections

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  • Last reply by Matt

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HI, First we are in Australia and we have Optus for our email client/company. We have laptops. My husband's is a ASUS Zenbook running windows 11. I have an HP running windows 10. MY emails work fine. My husband's do not. The settings are the same on both our laptops for the outgoing server, and remember mine works fine, but not his. So why do you think that he cannot send the emails? They go through sometimes though. Last one was on 20 Dec 2022. But not today, 19 Jan 2023. It very frustrating as you can imagine. AND yes, we have it set up as per Optus instruction, but remember, MY emails can be sent. I'm thinking of deleting Thunderbird and reinstalling it, but not sure. I'm also thinking of going over to Outlook, but don't really like them. Can you help please? Cheers, Sandy

HI, First we are in Australia and we have Optus for our email client/company. We have laptops. My husband's is a ASUS Zenbook running windows 11. I have an HP running windows 10. MY emails work fine. My husband's do not. The settings are the same on both our laptops for the outgoing server, and remember mine works fine, but not his. So why do you think that he cannot send the emails? They go through sometimes though. Last one was on 20 Dec 2022. But not today, 19 Jan 2023. It very frustrating as you can imagine. AND yes, we have it set up as per Optus instruction, but remember, MY emails can be sent. I'm thinking of deleting Thunderbird and reinstalling it, but not sure. I'm also thinking of going over to Outlook, but don't really like them. Can you help please? Cheers, Sandy

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Usually that sort of error comes down to something in the antivirus program in use. If both your settings are the same and you use the same modem/router to access the Optus service.

There have been issues with office365 where those with IPV6 enabled are having issues and that would be more likely on windows 11 than 10 I would guess. There is a network.dns.disableIPv6 pref which can be accessed via the config editor which will allow you to turn it off temporarily (or permanently) to see if that might be the issue.

BTW Hi from the Flinders, where I am looking for an alternative to the NBN.