OLD File Extension

What is the .OLD file type?

Meaningfully concise, the filename extension .old has become a conventional method of denoting backup copies across many operating systems and platforms. Whether appended manually or in a programmatic way, the .old suffix designates a filesystem entity (either file or folder) which is excluded from use and kept for backup purposes and also to revert any later changes made to it, if necessary. It may be a document, a configuration file, a system or user's folder, or any other data file. A most notable example would be the Windows.old folder created as a backup during the upgrade or repeated installation of the Microsoft Windows operating system. The .old filename suffix is also often manually added when making changes in important configuration files so as to keep the old, unaltered version intact.

Extensions like .old just designate the file's or folder's role, without providing any clues as to the file's true internal format or purpose. In cases of files, the .old extension is normally simply appended to the original filename and extension, making the actual file type evident and easily restorable.

Software to open or convert OLD files

Notepad++ by Notepad++ Team

 

PSPad editor by Jan Fiala

 

Internet Explorer

 

VLC media player by VideoLAN

 

NoteTab Light by Fookes Holding Ltd

 

Free File Viewer Pro

Download