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Thunderbird gives SMTP and IMAP errors since changing the modem

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vecchias
vecchias
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Hello,

I have been struggling with this problem for the past week. At first I couldn't even find the possible reason for IMAP SMTP errors I was receiving but then when I went outside to work at a cafe, and my Thunderbird was receiving/sending mail just fine again for my two gmail accounts, then it finally occurred to me that last week my modem was changed by my ISP. It is now a Huawei HG255s. And I've been doing some serious digging in the forums etc. to no luck.

I tried following: 1- Turning Firewall on/off 2- Disabling IPv6 3- Checking that less secure apps are enabled on google 4- Changing SMTP port to 587 (with STARTTLS instead of SSL/TLS) 5- Tried to check forwarding settings of the modem but lack of knowledge stopped me going any further

I cancelled all 2-step verification on my gmail accounts. And the weird thing is sometimes my Gmail A account receives/sends just fine, but Gmail B keeps on failing spectacularly.

And as a cliffhanger; I tried setting up a Yahoo account on Thunderbird and IT WORKS JUST FINE.

Thank you very much in advance, any help or advice that would get me to the solution will be much appreciated.

Hello, I have been struggling with this problem for the past week. At first I couldn't even find the possible reason for IMAP SMTP errors I was receiving but then when I went outside to work at a cafe, and my Thunderbird was receiving/sending mail just fine again for my two gmail accounts, then it finally occurred to me that last week my modem was changed by my ISP. It is now a Huawei HG255s. And I've been doing some serious digging in the forums etc. to no luck. I tried following: 1- Turning Firewall on/off 2- Disabling IPv6 3- Checking that less secure apps are enabled on google 4- Changing SMTP port to 587 (with STARTTLS instead of SSL/TLS) 5- Tried to check forwarding settings of the modem but lack of knowledge stopped me going any further I cancelled all 2-step verification on my gmail accounts. And the weird thing is sometimes my Gmail A account receives/sends just fine, but Gmail B keeps on failing spectacularly. And as a cliffhanger; I tried setting up a Yahoo account on Thunderbird and IT WORKS JUST FINE. Thank you very much in advance, any help or advice that would get me to the solution will be much appreciated.

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vecchias
vecchias Umnikazi wombuzo
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Hello!

Thank you very much for your reply. Yes I changed to 587 with STARTTLS with OAuth2. And less secure apps are allowed (although it wasn't before the new modem and was perfectly operational)

And yes I completely removed my two accounts, including AppData profile folders (it was probably unnecessary). I wasn't able to fetch the mails when I was trying to re-configure accounts at home. It was completely blank. They were downloaded once I was connected to a cafe's WiFi.

The weirdest thing is sometimes during the day TB connects, downloads data. Then goes back to prompting IMAP and SMTP errors.

And I've made a new discovery right now; one of my gmail accounts is -almost- working but the other gmail account is constantly giving me SMTP error when I try to send mails.