The ASD extension is used by Microsoft Word version 95 or later for auto-save files. Word stores the edited document independently at regular, adjustable intervals. Files with the extension ASD are created in the temporary directory. These files are deleted when the document is saved properly.
However, if Word did not correctly save a document due to an error or crash, this backup file can be used to restore the document. This usually happens automatically. It can also happen that this does not happen, then you can search for the ASD file and load it with Word (show all files).
Most often resolving problems with opening ASD files is very simple. Just install an appropriate program that supports such files. All of the listed programs support ASD files, but may vary in offered function and purpose. Some programs may be capable only of viewing contents of ASD files or offer file conversion options, but may not be capable of editing such files.
It is possible that although a compatible program has been installed on user’s system, it is not used by the system to open it. This may happen because no default application was associated with this type of files. To associate ASD files with given application, select "Open with" from drop-down menu (accessed by right-clicking on the file). Then select from the list the program or application you want to be used to open this type of file. If the Microsoft Word applications is not on the list, select "Browse" option in order to manually locate the directory where Microsoft Word has been installed.
Sometimes problems with opening ASD files may not lie with the application itself, but can arise due to other causes, such as: