Hi @Melker Karlsson ,
I suggest you go to Windows Settings > Apps > Default Apps, make sure Outlook desktop client is the default app by file type and by link type.
Then go to Registry Editor, navigate to Computer\HKEY_LOCAL_MACHINE\SOFTWARE\RegisteredApplications
, ensuer there is a string Outlook.Application.16
with value of "Software\Microsoft\Office\16.0\Outlook\Capabilities".
Besides, go to Computer\HKEY_LOCAL_MACHINE\SOFTWARE\Clients\Mail
, ensure there is a string (Default)
with value of "Microsoft Outlook".
If you can find Clients\Mail entry under HKEY_CURRENT_USER\SOFTWARE
, please also make sure its string (Default)
with value of "Microsoft Outlook".
Serious problems might occur if you modify the registry incorrectly. Before you modify it, please remember to back up the registry for restoration in case problems occur.
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