Work can be lost in a variety of ways, from computer crashes to power failures to and human error. Technology is notorious for finding ways to cause problems when it comes to data, and it can feel as though it has a tendency to fail more often if the data in question is more important. Sometimes, however, the data can be lost if changes were made to a document, then saved over. If you cannot undo the changes to a saved Word document, it is still possible to look for other, unchanged versions of the document.
Search for all versions of the document in question. In Windows XP, click "Start," then click "Search," and in Windows Vista/7, use the "Start Search" box. Modifying your search preferences to look in more locations may yield a larger number of results. Search for both DOC and DOCX files to maximize your search results.
Search for backup files of your Word document. Look in the folder your document is saved in and search for a file with a WBK extension. This is a backup file of your document, and you can open it with Word to view the older version of the document. If you don't see one there, go back to the Search utility in Step 1 and look for files with the WBK extension.
Search for auto-recovered files by looking for files that have an ASD extension. These usually display when you open Word, but if none are displayed, you can still search your whole hard drive for these files.
Search your hard drive for any temporary files. By clicking on "Search Options," you can modify your search preferences to look for any temporary files that were updated within a certain set of days. Search for all files with the TMP extension within the date parameters of your choice.
Despite these methods of finding other versions of Word documents, it is impossible to guarantee that an older version can be found every time. Some documents are simply lost, or changed, for good.