IMAP Duplicate e-mails

[fggs]

Good evening,

I have 2 IMAP accounts with latest Thunderbird (52.1.1 32-bit as of today). I usually leave my home computer on, with Thunderbird opened, but as soon as I open the Thunderbird (same version) from my work computer, which has the same IMAP accounts, I start to get duplicated e-mails.

I don't have any addons installed, but I do have a few message filters.

Doing a research on this forum, I saw a topic which says this could be caused by offline synchronization, I didn't try to disable it yet, but could this be the cause?

Thank you!

[tanstaafl]

Unlikely. Use control->U or view message source and compare the Message-ID: header value for two copies of the same message. Does that header have the same value in each copy?

Message-ID: <9efefc4b-cd10-89e5-7138-355a2576788d@gmail.com> is an example of that header.

Does each account have the same problem? Are they from different email providers?

http://kb.mozillazine.org/Duplicate_messages_received

[fggs]

Yes, both accounts have the same problem and they are from different email providers.

I will check the Message-ID header and report back, thank you!

[fggs]

Yes, the Message-ID header have the same value in each copy, just confirmed!

[tanstaafl]

That eliminates one possibility. Who are your email providers?

I assume you have windows search integration disabled in tools -> options -> advanced -> general. You could try disabling offline folders and global search/indexing and see if the problem still occurs. That should get rid of all of the background processes. If you disable just offline folders the global search/indexing will download them itself, rather than fetching them from the offline folders.

[fggs]

How do I disable the offline folders? Windows Search integration was disabled on both, just disabled global search/indexing, do I need to restart the client? Thanks!

[tanstaafl]

Uncheck tools -> account settings -> account_name -> synchronization & storage -> keep messages for this account on this computer. I suggest you restart TB afterwards.

[fggs]

Thank you! I did that on both Thunderbirds, but I still got a duplicated e-mail, it doesn't always happen, I'm out of ideas

[tanstaafl]

Create a new folder and copy a few messages to it. See if it has the same problem. The reason I suggest this is perhaps some of your folders are corrupted. Your symptoms don't really sound like that is the cause, but we're running out of things to check.

Does the problem only occur if you use both computers to check your mail?

Can you duplicate the problem if you use webmail (browser) instead of the second computer?

Are you also using a smartphone or tablet with that account?

Who are your email providers? I'm NOT asking for the email address, just whether you're using Gmail, Zoho, Outlook, GMX etc.

[fggs]

Does the problem only occur if you use both computers to check your mail?

Yes, only when I have Thunderbird opened on both computers

Can you duplicate the problem if you use webmail (browser) instead of the second computer?

The issue doesn't happen if I use webmail

Are you also using a smartphone or tablet with that account?

No, only those 2 computers which runs Windows 10 x64

Who are your email providers? I'm NOT asking for the email address, just whether you're using Gmail, Zoho, Outlook, GMX etc.

Sorry, I should have answered this a few messages above, both providers are local providers from Brazil, Locaweb and Terra.

[tanstaafl]

I suggest you add a Gmail IMAP account and see if you have the same problem with it since this is starting to sound like a email provider specific problem. I'm not suggesting it as a workaround, its just for troubleshooting.

http://kb.mozillazine.org/Gmail

[fggs]

Thanks for all your help tanstaafl!

After analyzing this carefully all night, I came to the conclusion this only happens with messages that passes through the message filters and moved to other folders, can this be a race condition or something?

[tanstaafl]

Seems unlikely. See if its a side effect of some add-on that doesn't work well with 52.1.1 by retesting after "help -> restart with add-ons disabled".

[fggs]

As I stated in the first message:

I don't have any addons installed, but I do have a few message filters.

The issue still occurs..

[fggs]

Found this: https://bugzilla.mozilla.org/show_bug.cgi?id=573729

But I don't know which information is lacking, should I reopen?