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cannot receive or send e-mails

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Hi all Since 26/09/2023 I haven't been able to receive or send emails on my main dektop PC. At first when trying to download e-mails I got a "Secure Connection Failed" error. I was using version 115.15.1(?) It has since updated to version 115.3 and the error message hasn't re-appeared, although I still can't send or receive anything. When I try to send an email I get this message: Sending of the message failed. The message could not be sent because connecting to Outgoing server (SMTP) relay.plus.net failed. The server may be unavailable or is refusing SMTP connections. Please verify that your Outgoing server (SMTP) settings are correct and try again. I have a laptop where I have copied all the account settings across to and that works perfectly. (on the same internet connection)

I am using Win 10 64 bit with Thunderbird 64 bit and Kaspersky IS, with Mozilla as an exception in the firewall settings.

I am a bit of a numpty with email programs, so have no idea where to start.

Regards Keith

Hi all Since 26/09/2023 I haven't been able to receive or send emails on my main dektop PC. At first when trying to download e-mails I got a "Secure Connection Failed" error. I was using version 115.15.1(?) It has since updated to version 115.3 and the error message hasn't re-appeared, although I still can't send or receive anything. When I try to send an email I get this message: ''Sending of the message failed. The message could not be sent because connecting to Outgoing server (SMTP) relay.plus.net failed. The server may be unavailable or is refusing SMTP connections. Please verify that your Outgoing server (SMTP) settings are correct and try again.'' I have a laptop where I have copied all the account settings across to and that works perfectly. (on the same internet connection) I am using Win 10 64 bit with Thunderbird 64 bit and Kaspersky IS, with Mozilla as an exception in the firewall settings. I am a bit of a numpty with email programs, so have no idea where to start. Regards Keith

Chosen solution

I have fixed it. (fingers crossed)

Although Kaspersky hasn't shown any obvious reason why it could affecting it, I downloaded and installed a new version as I had already bought a licence code for another couple of years and was due to add that to the software.

It now appears to all work correctly as I have tried it over the last hour or so and it's still working.

Thanks for the suggestions

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All Replies (13)

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No suggestions at all?

Looks like I'll have to find something else for my e-mails I used to use MS Outlook (nor Express!) but came to T'bird many years ago and never had a problem, until now.

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If it works on the laptop but not the desktop, it suggests an external app, most likely Kaspersky, is blocking outgoing mail. Run Windows in safe mode (don't just 'disable' Kaspersky) to test for startup app interference.

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Hi I ran Windows in Safe Mode and nothing came up showing a problem. What/Where should I be looking?

Keith

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KeithN said

Hi I ran Windows in Safe Mode and nothing came up showing a problem. What/Where should I be looking? Keith

Do you mean there were no errors, sending or receiving, with Windows in safe mode?

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Sorry I meant nothing that I haven't had before

When I try and receive nothing happens When I try and send I get the following error.

https://assets-prod.sumo.prod.webservices.mozgcp.net/media/uploads/images/2023-10-18-10-43-18-c2239a.png

If I try and update Tbird, it says "failed to check for updates"

I have just spent a fair time setting up the e-mail from scratch in supervisor mode in Windows. Nothing different from normal use.

Modified by KeithN

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Sorry I meant nothing had changed from normal use

When I try and receive, nothing happens, no errors shown but no emails. When I try and send I get the following error

https://assets-prod.sumo.prod.webservices.mozgcp.net/media/uploads/images/2023-10-18-10-50-51-c2239a.png

Tbird wont update either, it comes up with the error "Failed to check for updates" (it's set to auto update)

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I have just done a manual install of the latest version 115.3.3 After install it worked perfectly sending and receiving mail OK. It was also able to check for updates correctly.

After 5 mins it went back to fault mode and it again says "Failed to check for updates"! . What is going on?

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If it worked 5 mins. ago, it indicates TB is configured properly, but the subsequent failure suggests a problem at the server end. Perhaps contact Plusnet to confirm their server status.

Confirm also that you have relay.plus.net on 587, STARTTLS security, authentication = normal password, User Name = email address.

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All the settings are correct and another computer with the same settings works just fine.

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Chosen Solution

I have fixed it. (fingers crossed)

Although Kaspersky hasn't shown any obvious reason why it could affecting it, I downloaded and installed a new version as I had already bought a licence code for another couple of years and was due to add that to the software.

It now appears to all work correctly as I have tried it over the last hour or so and it's still working.

Thanks for the suggestions

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I tried uninstalling and reinstalling 3 times...no luck so I tried removing then adding each email account and BINGO!! Give it a go.

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See my previous reply. It is now working fine and marked as the solution.

There appeared to have been some corruption in Kaspersky as even in safe mode with peripherals off (?), it was still faulty but a new version cured the problem and also an extra problem that had appeared in Kaspersky itself, post the T-bird e-mail problem.

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Fair comment KeithN but I use TotalAV. Maybe the same cause for emails not being received but my ( eventual ) solution might be an easy fix for non-Kaspersky users.