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TBird steals my default email

  • 5 replies
  • 1 has this problem
  • 17 views
  • Last reply by Toad-Hall

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I have Outlook for business, and used to be able to use TBird for personal on Windows 10. When I changed computers (Win11 now, and Office 2023) and installed TBird, (and yes, UNchecked the "make default) on set up), TBird steals my default. This is when I am trying to email a pdf or spreadsheet, etc. where I click the email button and it generates an email with the file name as the subject. Rather than using my default Outlook (business account, mind you), the file opens in TBird. I've gone through every default in Windows, and cannot seem to locate a means of changing it in the INSTALLED version of TBird. I've uninstalled, and reinstalled multiple times ... all with the same results. Can anyone give me some insight, please? Teri HendersoTL@gmail.com

I have Outlook for business, and used to be able to use TBird for personal on Windows 10. When I changed computers (Win11 now, and Office 2023) and installed TBird, (and yes, UNchecked the "make default) on set up), TBird steals my default. This is when I am trying to email a pdf or spreadsheet, etc. where I click the email button and it generates an email with the file name as the subject. Rather than using my default Outlook (business account, mind you), the file opens in TBird. I've gone through every default in Windows, and cannot seem to locate a means of changing it in the INSTALLED version of TBird. I've uninstalled, and reinstalled multiple times ... all with the same results. Can anyone give me some insight, please? Teri HendersoTL@gmail.com

All Replies (5)

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What is the 'default apps' setting for MAILTO?

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Everything is set to Outlook.

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Please check registry key: HKEY_CURRENT_USER\Software\Clients\Mail

Exit Thunderbird.

'Start' > Run > type regedit or type regedit in the windows search and select 'Registry Editor' Locate this registry entry:

  • HKEY_CURRENT_USER\Software\Clients\Mail

on right side under 'Name' column double click on the word 'Default' Does it say Mozilla Thunderbird' in the 'Value Data? If yes, remove 'Mozilla Thunderbird' and Type 'Microsoft Outlook' in 'Value Data' click on 'OK'

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I keep having this problem, too.

I've used the options above and changed the registry. It seems to work, because Outlook comes up when I click a MailTo link but I still see Thunderbird in my Windows settings by protocol. See attachment. I'm concerned that this might destabilize applications in future that still refer to this setting. I would like to set this correctly, but nothing else I've tried works.

Why??? It's strange that Thunderbird hijacks this setting when installing. Does it not give the user the choice when installing the app. Many people already use another mail client and Thunderbird is a secondary client.

Thanks in advance for any help.

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When you install programs various registry keys get set up automatically and it may depends upon which app you installed first and secondary as to what settings get put into or overwritten in the registry.

When you set the default app it is the Operating System which sets the registry settings.

In Windows OS - in bottom search type : default and choose 'Default Apps' This allows you to choose the default app for 'Email' scroll down to see text link for: 'Choose default applications by protocol' - click on it. This is where you see 'MAILTO' and where you can choose the default 'mailto' app. These settings are set up by the Operating System and they should override everything. But clearly the OS is not setting up the patricular Registry Setting which I instructed to alter. Windows help forums via the internet have tons of complaints going back several years regarding this particular problem and it's never been fixed. It all kicked off with MailTo issues because the registry settings got modified by Microsoft as they created additional registry settings. I could rabbit on about it but this link provides a reasonable explanation. https://superuser.com/questions/1045349/where-windows-10-stores-default-email-app-in-its-registry/1119010#1119010

So the problem you have is not Thunderbird, you could be using any email client even the default 'Mail' and you will find the OS does not seem to get that registry setting correct.

Hence why I gave information on how to do it directly via Registry Editor.