.OLD File Extension
File TypeBackup File
File format categories include Binary, Text, XML, and Zip. The format of this file type has not been determined.
Typically used as an indicator for a backup copy of a file; appended to the filename when a newer version of the file has been created or saved by a certain program; often placed after the original file suffix (i.e. document.doc.old would be a backup copy of the file "document.doc").
May be created automatically by a software program, but may also be created manually by the user. The ".old" extension may have to be deleted in order for the file to open correctly.