Recover lost data in .tmp files
It's common to find .tmp files in Windows folders. Most people ignore them or delete them. But the e-discovery professional should be sure to note that data can be recovered from these temporary files. See figure 1 below. A .tmp file located on my hard drive was opened in NotePad. It revealed the contents of an old file in which I had saved notes on how to run a query for multiple documents in Concordance.
If you're hunting for lost MS Word or MS Excel files, you may be able to recover some of the raw data from them in .tmp files saved to a location such as: C:\Users\[username]\AppData\Local\Temp in Windows 7.
See this web site for more information: http://office-recovery.com/
It recommends focusing on files which begin with a tilde, ~ , and states that Word files will often be saved to a .tmp file beginning with ~wrd, ~wra, OR ~wrf, and data for Excel files will often be saved in .tmp files only using digits in the file name or beginning with ~dfx. I could not however find examples such files on my personal or work PCs.