If you notice that your Excel files are opening in Notepad, then read this post to learn how to fix the issue. The default behavior of a document or file is to open in the application with which ...

Attackers can attempt to hide malicious payloads in Excel files sent by e-mail by using a standard Excel feature, according to a Tuesday post by Mimecast researchers.

If you see The file couldn't open in protected view error while opening Microsoft Excel, the fixes listed in this post will help you.