"WIM" stands for Windows Imaging Format file. This format is a disc image type used to store multiple other disc images into one file. Disc image files are electronic backups of physical CDs. If you want to install a WIM on your computer, you'll first need to mount the file using a virtual CD program. This is the electronic version of putting a CD in a CD-ROM drive.
Download and install a WIM mounting program, like WinMount. Click "File."
Select "Mount WIM file."
Double-click the WIM file to mount it. The file will now be recognized as a CD would be when you put it in the CD-ROM on your computer. Click "Install" in the autoplay screen to install the WIM.