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Thunderbird opens emails in write mode when double-clicked from account's inbox/root folder

  • 10 replies
  • 1 has this problem
  • 1 view
  • Last reply by Marks

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Hello everyone, I hope you all are safe in these hard pandemic times.

I am having almost the same problem as of question #1245998. But that topic is archived so I must open this new one because, well, the problem is still there.

I'm using Thunderbird 68.9.0 (32 bit) on Windows 10 Pro 64 bit version 1909. I have no extension installed.

The issue is: Thunderbird opens emails in write mode when double-clicked from account's inbox/root folder. The new mail is opened with my own email address as "To:" recipient, and the following error message appears at the bottom of the email window: "A unique identity matching the From address was not found (...)".

The issue occurs when:

  • I double-click an email located in the root (Local folders).

Everything is fine (i.e. email correctly opens in a new tab) when:

  • I right-click on an email and select "open in a new tab" (free translation of my Italian version!);
  • I open an email which is in a subfolder of root.

I've already tried to:

  • uninstalling / reinstalling Thunderbird;
  • erasing xulstore.json and session.json in the profile folder;
  • launching Thunderbird in safe mode;
  • setting "open in a new window" and then setting back "open in a new tab" in Tools > Options > Display(?) > Advanced.

Since the "double-click" is the standard/preferred email opening method (and since this is clearly a bug in the first place) it would really be great if there was a way to fix the issue.

Thanks! Marco

Hello everyone, I hope you all are safe in these hard pandemic times. I am having almost the same problem as of [https://support.mozilla.org/en-US/questions/1245998 question #1245998]. But that topic is archived so I must open this new one because, well, the problem is still there. I'm using Thunderbird 68.9.0 (32 bit) on Windows 10 Pro 64 bit version 1909. I have no extension installed. '''The issue is''': Thunderbird opens emails in write mode when double-clicked from account's inbox/root folder. The new mail is opened with my own email address as "To:" recipient, and the following error message appears at the bottom of the email window: "A unique identity matching the From address was not found (...)". '''The issue occurs when''': * I double-click an email located in the root (Local folders). '''Everything is fine (i.e. email correctly opens in a new tab) when''': * I right-click on an email and select "open in a new tab" (free translation of my Italian version!); * I open an email which is in a subfolder of root. '''I've already tried to''': * uninstalling / reinstalling Thunderbird; * erasing xulstore.json and session.json in the profile folder; * launching Thunderbird in safe mode; * setting "open in a new window" and then setting back "open in a new tab" in Tools > Options > Display(?) > Advanced. Since the "double-click" is the standard/preferred email opening method (and since this is clearly a bug in the first place) it would really be great if there was a way to fix the issue. Thanks! Marco

All Replies (10)

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  • Errata corrige:

where I wrote "Local folders" I actually meant "account's root folder"

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Check in account settings > copies and folders where drafts are supposed to be placed. Whatever folder is specified will open in write mode. (This is normally the drafts folder)

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Matt said

Check in account settings > copies and folders where drafts are supposed to be placed. Whatever folder is specified will open in write mode. (This is normally the drafts folder)

Hello Matt, thanks for taking the time.

In my "account settings > copies and folders" , the option "Keep drafts in:" is set to "Drafts folder in (accoutName)".

Why should this affect the messages in the root (inbox) folder?

I forgot to mention that the issue I'm talking about has begun showing up just yesterday; before then, TB was working as expected, opening inbox messages in the normal/read mode.

Modified by Marks

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Is this a POP or Imap mail account?

Do you see an empty Inbox folder in the 'Local Folders' mail account? If yes, do you recall this appearing recently ?

Do you have any Pop mail accounts set up as deferred accounts, more commonly called 'Global inbox' where all incoming mail is collectively put into 'Local Folders' mail account 'Inbox' folder?

If you do not use 'Global Inbox' and you can see an empty 'Inbox' in 'Local Folders' mail account then do this:

In Thunderbird

  • Help > Troubleshooting Information
  • click on 'Open Folder' button

A new window opens showing contents of 'profile name' folder.

  • Exit Thunderbird now.
  • Click on 'Mail' folder
  • click on 'Local Folders' mail account.
  • Delete 'Inbox' and 'Inbox.msf' files and if you see a 'Inbox.mozmsgs' file then delete that as well.

Start Thunderbird.

Please report back on results.

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Hello Toad-Hall,

the account is POP, it's the only one set in TB and no, in the 'Local Folders' account there's no 'Inbox' folder (just the trash and 'Outbox').

The only existing account is set to store incoming messages in its own 'Inbox' folder (Account settings > Server settings > Message storage > Advanced).

For the sake of curiosity I've just opened the 'Mail' folder inside profile's folder, and in the 'Local Folders' which is there there's some content, specifically a portion of (myaccount)'s Inbox.

But neither 'Inbox' nor 'Inbox.msf' or 'Inbox.mozmsgs' are present.

As an experiment I've tried moving elsewhere that whole 'Local Folders' folder inside 'Mail' and restarted MB.

It did not solve the issue; the only difference is that the 'Local Folders' inside 'Mail' was recreated, just without all that partial content that was there before (just some default .msf anf non-.msf files).

Modified by Marks

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The 'Mail' > 'Local Folders' folder should have 'UnsentMessages' and 'UnsentMessages.msf' because these are for the 'Outbox' folder and obviously 'Trash' and 'Trash.msf'.

re :and in the 'Local Folders' which is there there's some content, specifically a portion of (myaccount)'s Inbox.

  • Could you post an image of contents of Local Folders before and after?
  • Please clear cache. Options > Advanced > Network & Disc Space


  • Exit Thunderbird.
  • Access Profile name folder.

Delete these files

  • folderTree.json
  • panacea.dat
  • session.json
  • xulstore.json

Start thunderbird.

Please report back on results.

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Cache cleared, TB closed, the 4 files erased, TB restarted.

The issue is still there.

Attached: the contents of the 'Mail' folder inside my profile's 'Local Folders', before (left) and after (right) moving the entire 'Local Folders' away and its automatic recreation.

All that's blurred are personal subfolders (.sbd) or files (.msf).

Modified by Marks

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In the 'profile name' folder

  • Click on 'Mail' folder

Do you see more than one pop mail account name folder, perhaps one has a number appended?

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No, there are only 'Local Folders' and the one pop mail account which I'm using; it is 'pop3s.(myMailProvider)'.

Modified by Marks

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Adding to the mistery:

I've tried creating another POP account alongside the aforementioned one, and I made subfolders into it as well.

All emails in this new account opens correctly both in the root/inbox folder and in the subfolders...

The 2 accounts are configured exactly the same.

I'm a bit confused :-)