The log files are stored in My Documents/Documents as RTF file format. If you've deleted them, then you need a recovery solution to use for this procedure. Luckily, there are plenty of these apps released and ready to be used. One of them is Recuva and it can be downloaded through the app page at Software Informer.
Download and install the software then use the startup Wizard to configure the scanning procedure. Choose the location, Deep Scan (might increase accuracy) and the file type. Scan for files and after you recover them, right click each one in the search results window and restore it to another partition different than original one.
