Hi again - Here is the message box I referred to above. One other behavior that I noticed, if I have more than one message that fails (unusual, but it happened again today) Thunderbird will create a local sent folder for each message. Odd...

--Sam

Are you using one of the "big" providers for mail?

I have been hearing about yahoo needing to have the max number of connections reduced from 5 to 3 in the server settings advanced over the past couple of weeks and wonder if it may be Thunderbird is attempting to many connections at the same time. You might want to try changing the valueit and report your results. (more usually means faster, but not if it messes other things up.)

Hi Matt - No, my domain(s) are hosted on Dreamhost and I'm on their IMAP mail servers. What is the setting you are referring to? Is it the "maximum number of server connections to cache" setting? --Sam

What is the setting you are referring to? Is it the "maximum number of server connections to cache" setting? --Sam

That is the one, It is a long-shot. But there is something happening with getting sent messages to the sent folder. This dialog was an attempt to prevent the data loss that occurs when it just fails, as otherwise you would have no record. But the send also created an additional connection to the IMAP server to update the sent folder, hence my long-shot.

I have a sneaking suspicion that it might be related to network monitors from things like anti virus products that are overloaded at that point scanning new files (temp of thee mail you send), updated files (the profile folders local sent folder) and network traffic (the send on port 465 and the IMAP traffic traffic on port 993 all essentially happening at the same time.

Ok - got it. The "data loss" catch certainly worked (that was a good idea). But TB is certainly working - the messages are being sent after all.

I'll change from 5 to 3 and see if there is an obvious change (like it works :-). It might take a couple of days. (I wish I could force this error, but I haven't figured out how). I'll repost results here.

Thanks again. --Sam

It might take a couple of days. (I wish I could force this error, but I haven't figured out how). I'll repost results here.

I have only ever seen the error once in over 10 years of using Thunderbird. It makes trying to determine the cause most difficult.

Hi again - Just an update. Reducing the number of connections cached did not have the desired impact. I still get the saving to local folders dialog.

Also, I happened to get an update pushed (but after the error) - I'm now on 78.14.0 (64-bit). So for now, I'll do nothing and see if this little gremlin went back where it came from. Again, it might take a couple of days to test it.

do you have anti virus scanning encrypted connections. The issue is a network error, probably a timeout. if there is scanning it may be slowing things enough to mess the copy.

Hi Matt - not that I'm aware of. My ISP is Spectrum and locally I just run Windows 10 AV. I do have the advanced security turned on - kernel protection, key files, and ransomware. But I haven't changed anything in a year or more. Of course it does update and Microsoft would _never_ make a change and not tell me - right ;-)

I'm about ready to move this to the "wait until TB 92 comes out" pile. I plan to do a fresh install when 92 comes out and just bring over my archives. Maybe that will resolve it some magical way.

FWIW, I put in a trouble ticket against the Dreamhost IMAP service to see if they have any ideas. I'll update that with your AV scanning point. If I get anything more on this, I'll post back here.

 *\_(oo)_/*

Thanks again for your help!!

Try running through the following to see if resetting works.

Reselect the 'Sent' as subcribed:

• Right click on imap mail account name folder in Folder Pane and select 'Subscribe'
• Click on 'Refresh'
• Select the 'Sent' folder - make sure it has checkbox selected and click on 'Subscribe'.
• Click on 'OK'

Now check the account:

• Right click on imap mail account name folder in Folder Pane and select 'Settings'
• Select 'Copies & Folders'
• Select 'Place a copy in'
• Select 'Other' and choose the 'Sent folder on the imap account' option.

Then check what is currently selected to be downloaded:

• Click on 'Synchronisation & Storage'
• Select checkbox 'keep message in all folders for this account on computer'
• click on 'Advanced..' button
• Make sure the 'Sent' folder has checkbox selected.

Restart Thunderbird and attempt to send an email.

Please report back on results.

Hi Toad-Hall - Thanks for your ideas. I completed the steps you described. The message sent fine and is placed in the IMAP sent folder. This was what I expected.

There has never been a problem with TB sending messages manually or when running the filters manually after TB startup is complete. The issue only occurs during start-up when the filters run automatically. I think this is the genesis of Matt's thought that it's a network issue. Once TB settles down and I use it at human speed (versus automation) it works as expected.

FWIW, previously I did try disabling the existing filters and recreating them with slight changes in parameters (different email address, change in conditions). There was no change in TB behavior.

I'm really just kind of glad that someone (dev) thought to put that dialog box in for this condition. After all, the messages are being sent - and I know what's happening. How that person ever got to "Hey, maybe I should catch this." I don't know, but it's one of the many thing about TB that make it great.

--Sam

Matt & Toad-Hall - I never have been known to give up entirely, so I did this.

On Sunday I deleted the offending IMAP account in TB, including all settings, and filters (and anything else I could think of - except uninstalling TB). I recreated the account (using default settings for IMAP with SSL/TLS for incoming and outgoing) and only the forwarding filters that have been causing this problem. The port assignments are normal - 993 & 465. This afternoon ~1330 EDT, the forwarding filters worked without error. I didn't even notice until I checked my IMAP sent folder.

This is kind of "over achieving" on Toad-Hall's "reset" recommendation and ensures that any inadvertent network or account settings have been restored to default. So thanks to you both. So far so good. Let's see if TB continues to behave. --Sam

All - So it's been a week since I fully recreated the offending IMAP account. Everything is working as expected. Filters are sending, no local folder warnings, outgoing mail is sent and then moved to the sent folder (on IMAP) as expected. So the "issue" is resolved.

Unfortunately, I feel like I used the nuclear approach to resolve it. It would have been nice to know what was actually not working. I appreciate the guidance, suggestions, and patience from Matt and Toad-Hall.

Regards, --Sam