When I turned on my computer today it said I was missing some seriously important files and Windows was unable to start.  This generally means a reinstallation of Windows is necessary and this process can take hours.  And it can be weeks before you are back to the way things were.  Here is the software that got me back online in record time. Here is what it took to get me back online: inserted a CD-ROM, plug in my external hard drive into my USB port, turn the power on, the Acronis program starts up independent of Windows, I choose which files and folders or disk partitions to restore, click the restore button.  Then I was good to go.  Maybe I should buy a real copy of the software.