Hi Chris,
>>but double clicking the attachment gives the message "We can't open 'c:\outlook temp file path\any type of file'.
If we right click the attachment and click Open, will the file be opened correctly?
Does it happen to all file types? Try checking your Windows file type associations.
What's the detailed version of Outlook 2019? Please install available updates to see the results. Refer to
this link.
Besides, we can also try opening Outlook in safe mode to see if the issue continues. Please exit Outlook, press Win key + R to open the Run command, type outlook.exe /safe and then press Enter. This helps eliminate whether the problem lies on any third
party add-ins.
Any updates, please feel free to post back.
Regards,
Perry
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