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Can't send message - error message states for unknown reason

  • 3 cavab
  • 1 has this problem
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  • Last reply by sfhowes

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Hello - Problem started when I set up my current email account that I use on desktop computer using Thunderbird on my iphone. Email on the iphone worked fine. But I did notice that sometimes I had to close the mail app on my iphone before I could use my email account on my desktop. I would get an error message email is locked due to an open session. Then it got to point that I couldn't use email on desktop whether email app on iphone was open or not.

I spent 2 hours on phone with internet service provider Spectrum (previously Time Warner Cable). We tried everything in account setting and options. We changed the password for my email account and I even deleted my email account on my iphone. Still getting same error message. After trying some other things repeatedly...I can now receive emails on desktop using Thunderbird but when I try to send an email I get this error message -

Sending of the message failed. The message could not be sent using Outgoing server (SMTP) mail.twc.com for an unknown reason. Please verify that your Outgoing server (SMTP) settings are correct and try again.

I've checked my outgoing server setting and they are what they should be.

So in summary problem started when I tried to use my email account on 2 devices, desktop computer using Thunderbird and iphone using Mail App. I have deleted email account on iphone, and changed my password on email account. I did this because some error messages I got referred to...can't retrieve password.

Any help would be greatly appreciated, Scott

Hello - Problem started when I set up my current email account that I use on desktop computer using Thunderbird on my iphone. Email on the iphone worked fine. But I did notice that sometimes I had to close the mail app on my iphone before I could use my email account on my desktop. I would get an error message email is locked due to an open session. Then it got to point that I couldn't use email on desktop whether email app on iphone was open or not. I spent 2 hours on phone with internet service provider Spectrum (previously Time Warner Cable). We tried everything in account setting and options. We changed the password for my email account and I even deleted my email account on my iphone. Still getting same error message. After trying some other things repeatedly...I can now receive emails on desktop using Thunderbird but when I try to send an email I get this error message - Sending of the message failed. The message could not be sent using Outgoing server (SMTP) mail.twc.com for an unknown reason. Please verify that your Outgoing server (SMTP) settings are correct and try again. I've checked my outgoing server setting and they are what they should be. So in summary problem started when I tried to use my email account on 2 devices, desktop computer using Thunderbird and iphone using Mail App. I have deleted email account on iphone, and changed my password on email account. I did this because some error messages I got referred to...can't retrieve password. Any help would be greatly appreciated, Scott

All Replies (3)

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What are you settings for the outgoing server? They should be mail.twc.com on port 587, with Connection security = None, authentication = password, transmitted insecurely and User name = email address.

When you changed the password, did you edit or remove the one stored in Tools/Options/Security/Passwords/Saved passwords?

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Hey sf - Thanks for your attention and help with my problem.

I checked everything you mentioned and found that I didn't have my email address in the user name field. Not sure how that happened, but with the 2 hours of troubleshooting with Spectrum CS I must have deleted it by mistake or on purpose and then not filled it back in later. We were trying a bunch of things in desperation.

So I guess I've learned that Thunderbird doesn't play well with the iphone mail app. Do you know of a work around on this? It would be ideal if I could get my email on both devices for my work.

Thanks again I truly appreciate you! Scott

I was planning on spending a good part of the day working to get me email back.

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It has been known for some time that the iphone mail app seems to make too many connections to an IMAP server that it makes access by TB impossible. I would first confirm you have the correct settings for TWC in TB before looking at the iphone. I don't know if this is a problem confined to the mail app, not having an iphone myself, but I encounter no such conflicts with several computers and phones accessing my accounts, where the mail app is either Outlook mobile or the gmail Android app. There is an iOS version of Outlook that might work better than the built-in mail app.