For Windows 11, open File Explorer, choose “View,” then “Show,” then choose “File name extensions” from the list. You don’t have to show file extensions for all files on your ...

Hide Extensions Is the Default Starting with Windows 8.1, the extensions on DLL, OCX and other Windows systems files are displayed even in the default hidden mode (left column).

The list, which previously included 104 file extensions, will be expanded "soon" with 38 new entries. These new entries are file types that are regularly used to deliver malware to Outlook inboxes.

Microsoft hides file extensions in Windows by default even though it's a security risk that is commonly abused by phishing emails and malware distributors to trick people into opening malicious files.