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Outlook 2019 and thunderbird

arkadiusz.szelagowskI
arkadiusz.szelagowskI
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maybe someone will help me, I use thunderbird version 78 on windows 10 pro, I have the impression that every time I start my computer, outlook (from office 2019) sets itself as the default client. I delete "HKEY_CURRENT_USER \ Software \ Clients \ Mail" Outlook keys in the registry, but new ones keep appearing. The default client itself also changes. How do I block it? Outlook alone cannot be uninstalled. I have thunderbird set as my default client wherever I can but that doesn't help. I tried to install office without outlook but failed. please help.

maybe someone will help me, I use thunderbird version 78 on windows 10 pro, I have the impression that every time I start my computer, outlook (from office 2019) sets itself as the default client. I delete "HKEY_CURRENT_USER \ Software \ Clients \ Mail" Outlook keys in the registry, but new ones keep appearing. The default client itself also changes. How do I block it? Outlook alone cannot be uninstalled. I have thunderbird set as my default client wherever I can but that doesn't help. I tried to install office without outlook but failed. please help.
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All Replies (2)

Toad-Hall
Toad-Hall
  • Top 10 Contributor
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HKEY_CURRENT_USER \ Software \ Clients \ Mail Set Default Data: Mozilla Thunderbird

But....what do you have here: HKEY_LOCAL_MACHINE\SOFTWARE\Clients\Mail It is possible you have 'PackagedMail' set as the default and that is Outlook. Change default to Mozilla Thunderbird


In Windows Search type : default and choose 'Default apps' Email should say Thunderbird

scroll down and click on 'choose default applications by protocol ' MAILTO should say Thunderbird

arkadiusz.szelagowskI
arkadiusz.szelagowskI Question owner
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Everything is consistent with what you wrote. The problem is that every few days a process or service changes the default mail client in the registry and adds new Outlook keys in the registry. For now I have manually deleted Outlook files and it's been ok for 4 days. I haven't figured out what causes the default client change yet, I suspect some windows updates or internal office processes.