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Thunderbird on Windows 10/11

Steve Hall
Steve Hall
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I supply software that uses TB to send emails with an attachment (via MAPI - an invoice) I have a number of customers for whom this has stopped working. I tested all of these with the usual fixes. The app has full access to the folder containing the file. The app is set as administrator and is inside the firewall. I have set default mail app to TB. TB is set to check as default on startup. Yet windows keeps saying we need to define a default email client. One customer solved the problem by buying a new PC. I have another customer who has this problem on a new PC. There may be a common denominator in Microsoft Office which on loaded onto the PC's. If that is the problem then that is Microsoft denying access to TB? Has anyone had this problem and can suggest a fix I would be grateful.

Steve Hall

I supply software that uses TB to send emails with an attachment (via MAPI - an invoice) I have a number of customers for whom this has stopped working. I tested all of these with the usual fixes. The app has full access to the folder containing the file. The app is set as administrator and is inside the firewall. I have set default mail app to TB. TB is set to check as default on startup. Yet windows keeps saying we need to define a default email client. One customer solved the problem by buying a new PC. I have another customer who has this problem on a new PC. There may be a common denominator in Microsoft Office which on loaded onto the PC's. If that is the problem then that is Microsoft denying access to TB? Has anyone had this problem and can suggest a fix I would be grateful. Steve Hall

All Replies (3)

sfhowes
sfhowes
  • Top 10 Contributor
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First thing to check is if the sending app, e.g. the invoice software, is 32 or 64-bit. If it's 32-bit, TB should also be 32-bit. The default TB installer for 64-bit Windows is 64-bit.

See also:

https://support.mozilla.org/en-US/questions/1323685

https://support.mozilla.org/en-US/questions/1400388

https://support.mozilla.org/en-US/questions/1419143

Helpful?

Steve Hall
Steve Hall Question owner
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This 32bit did not solve the problem! I have lots of 64bit versions working happily with 32bit app. Previous suggestions In Thunderbird Menu app icon > Options select 'General' 'System Integration' section select checkbox 'Always check to see if Thunderbird is the default mail client on startup'

In Windows 10 In 'Default apps' 'Email' needs to be set as 'Thunderbird'

scroll down click on 'choose default applications by protocol' MAILTO should be set up as Thunderbird.

ALL ABOVE SET I will try to see if mailto:fred@a.com, or right click in file explorer "send to mail recipient" works. Also suggested having a look at:- 

    HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\App Paths\outlook.exe
   HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\App Paths\thunderbird.exe

I will let you know how I get on.

Helpful?

Wayne Mery
Wayne Mery
  • Moderator
  • Top 10 Contributor
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sfhowes' question is spot on - is if the sending app, e.g. the invoice software, 32 or 64-bit?

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