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Thunderbird cannor receive or send emails - software block?

  • 9 replies
  • 1 has this problem
  • 6 views
  • Last reply by foxy.foxy

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I am using TB 68.8.0 (64-bit) on MacOS HighSierra 10.13.6.

I have configured TB to work with one Gmail account and four other accounts (mix of POP3 and IMAP). All was working fine until yesterday afternoon. Since then I cannot download messages or send any emails (from any of the accounts). When I click on 'Get Messages, I get an error message ('Could not connect to server....'). When I try to send an e-mail it says 'Sending of the message failed. The message could not be sent because connecting to Outgoing server (SMTP) ...... failed.'

All the server settings seem to be OK.

I have tried TB in safe mode. That does not help. If I boot the computer in safe mode, everything works. I read by googling this that programs in the background can block TG. I have not installed any new programs the last week. I have run an antivirus program (AVG Antivirus) and nothing seems to help.

Any help would be hugely helpful?

Thanks!

I am using TB 68.8.0 (64-bit) on MacOS HighSierra 10.13.6. I have configured TB to work with one Gmail account and four other accounts (mix of POP3 and IMAP). All was working fine until yesterday afternoon. Since then I cannot download messages or send any emails (from any of the accounts). When I click on 'Get Messages, I get an error message ('Could not connect to server....'). When I try to send an e-mail it says 'Sending of the message failed. The message could not be sent because connecting to Outgoing server (SMTP) ...... failed.' All the server settings seem to be OK. I have tried TB in safe mode. That does not help. If I boot the computer in safe mode, everything works. I read by googling this that programs in the background can block TG. I have not installed any new programs the last week. I have run an antivirus program (AVG Antivirus) and nothing seems to help. Any help would be hugely helpful? Thanks!

Chosen solution

I recommend you take a close look at the startup apps, since that is the likely explanation for why email stopped working:

https://www.macworld.com/article/2047747/take-control-of-startup-and-login-items.html

https://nektony.com/blog/mac-startup-items

Another, less likely possibility is that email works in OS X safe mode because the network adapter driver applied in normal mode is different from the (basic) one used in safe mode.

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All Replies (9)

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Suggest you try this:

Modified by Toad-Hall

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Hello,

thanks for the help, but sorry, no improvement.

any other bright ideas?

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Disable AVG in the login items, for a true test if it's the source of the problem:

https://support.apple.com/en-ca/guide/mac-help/mh15189/mac

Mail Shield may be just one component that needs to be disabled.

Other Mac users have had to change the setting in Preferences/Advanced/Network & Disk Space/Connection to one of no proxy, auto-detect or system proxy - which may be related to AVG interference.

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Dear sfhowes and Toad-Hall,

Thank you for your swift replies.

1. AVG is not a log in item. The only login in item I have is dropbox.

2. I installed AVG this morning (so after the problems appeared). I thought that maybe a virus could be source of my problems.

3. I recently installed the kernel BlackHole. Could that have an effect???

All suggestions are appreciated!

Best FF

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If AVG isn't a login item, and there's no option in its settings to disable it at startup, remove it and test.

As for BlackHole or VPNs or any other network app, yes, that could very well affect TB. You say that everything works in OS X safe mode - a good indication the problem is caused by non-TB apps.

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Dear sfhowes,

Thank you for your patience.

I have successfully de-installed AVG. Unfortunately, it did not help.

I am virtually certain that it is another program that blocks TB. Not only does it work in safe mode, but also couple of times when I have rebooted the computer, TB has been able to download messages and then it goes back to being totally unable to connect to internet.

I do not have a VPN, so its another program.

Again, any suggestions are welcomed.

Best,

FF

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hello again,

thank you for your time and your patience.

here is an update on what i have tried.

1. i logged into my computer as a guest user. here i tried to set up three accounts in TB. i had no luck with getting any of them to work.

i then went back to being my 'usual user.'

2a. i de-installed Blackhole. this meant that i was able to access mail (incoming) in two of the five accounts that i have in TB (one .gmail and info@mkponline.org) they are both IMAP. I was not however not able to get incoming mail for the other three accounts (one IMAP and two pop3).

2b. I was not able to send e-mail from any of the five accounts (they could not reach their smtp).

it all seems very curious to me. let me know if you have any ideas.

all the best + thank yooooou :-)

FF

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Chosen Solution

I recommend you take a close look at the startup apps, since that is the likely explanation for why email stopped working:

https://www.macworld.com/article/2047747/take-control-of-startup-and-login-items.html

https://nektony.com/blog/mac-startup-items

Another, less likely possibility is that email works in OS X safe mode because the network adapter driver applied in normal mode is different from the (basic) one used in safe mode.

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dear sfhowes,

thank you for the reading list. it helped me :-).

i am very pleased to let you know that my e-mail problems have been solved.

1. the 'good' bit:

the problem was connected to the strange 'virus' that i found earlier called "ExpertCharacterSearch." i am just not sure why the anti-virus program did not remove it...

in MacintoshHD/Library/LaunchDaemons

there were two items. one was called:

com.ExpertCharacterSearchP.plist

the second was called something similar.

all the strangeness that has plagued me these last days has had names with 'ExpertCharacterSearch' in them.

2. the naughty bit

it said on the website that you suggested (https://www.macworld.com/article/2047747/take-control-of-startup-and-login-items.html) that i should not touch anything in "Library/LaunchDaemons". but the name was too obvious.

this article gave me courage:

https://www.myantispyware.com/2020/02/20/how-to-remove-expertcharactersearch-from-mac-virus-removal-guide/

it was probably the wrong thing to do and i was REALLY worried when i rebooted the computer having removed the two plist. objects

but he who dares wins ;-)

thank you for the help!!!

FF