While "J&M123" is not a standard system file, similar naming conventions sometimes appear in specific contexts:
: You can often right-click the file and select Extract All or use the open-source 7-Zip tool to open it. J&M123.7z
: Developers often use such names for temporary ZIP or 7z backups. While "J&M123" is not a standard system file,
Since .7z is a compressed archive format, you cannot read the text inside without first decompressing or "unzipping" the file. : If you have the 7-Zip executable installed,
: If you have the 7-Zip executable installed, you can list the filenames within the archive without extracting them by using the command: 7z l J&M123.7z . Common File Associations
You can use 7-Zip on any computer, including a computer in a commercial organization. You don't need to register or pay for 7-Zip. 7z Format - 7-Zip 18 Documentation
If you are looking for the content of a file with this name that you currently possess, you will need to extract it using an archiving tool. How to Access the Text