Creating backups for important files helps insure you're covered if the file becomes corrupt or lost. Typically a backup file is zipped and stored onto the hard drive, so if you need to recover the backup file, you can easily open it and place it in the location of the original file. The installation process does not take a great deal of time, as long as you know where you stored the backup file.
Find the location of the backup file on your computer. It can be on a separate hard drive, CD or on the current hard drive.
Right-click the file if it is zipped and select "Unzip." This launches the zip software on your computer. If the file is zipped, you most likely have software that can extract the original file. If you do not, download a free trial version from WinZip (see link in Resources). You know the file is zipped if the folder icon has a zipper image on it. If the file is not zipped, skip to Step 4.
Set your computer desktop as the extraction point and click "Unzip" (or "Extract"). The backup file is saved to your computer desktop.
Close out all open windows and navigate to the location of the file you need to replace with the backup version.
Click and drag the file into the original location from the desktop and allow it to copy over. Close the window. The installation is finished.