A file with .asd extension is a Microsoft Word Recovery file that is generated automatically along with the main Word files. It is used to recover the original file if the Word application malfunctions or closes unexpectedly, resulting in the loss of data or main file. Microsoft Word can save all document file formats such as DOC, DOCX and others as the auto-recovery files. Word suggests the original file format and file name upon reopening the recovered file which it stores in system registry for recovery.
ASD File Format - More Information
The Microsoft Word Auto-Recovery files are saved to disc in binary file format alongside the main document file. These are usually saved to disc as hidden files with arbitrary names. All open files are actively and periodically saved to disc in order to meet the requirements of recovering at any time. When Microsoft Word is opened after a crash or unexpected closure, it automatically opens the last saved recovery file and suggest the original file name and extension for saving it back.
How to Recover Word File from ASD file?
ASD files created against the original files remain available alongside and are used to recreate the original document. If your Word file closes unexpectedly, you can open Microsoft Word or double-click your file and it will automatically ask you to recover the file that you can save with original file name and extension.