Using classic Outlook for Windows in business environments
Hello Pharoah, Jamie
Thank you for posting question to Microsoft Q&A Forum.
Please check on Q&A Assist's response - you might need to specify more about the attachment types, depending on it is a document, or an image, or something else.
Here is the screenshot of Settings > Apps > Default Apps:
For example, if it is a link, it should end as *.html file, you could change it to your preferred browser after searching for the word "html". This could result in opening any links in the browser you have chosen.
I hope this combines with Q&A Assist should help you. Please let me know if you have any further questions.
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