You can do this using Quicken cloud service. With the cloud service, they give you 5GB of data in your Dropbox account. There are 2 different files in Quicken that have the same file name. They will end in the file extension QDF. You will need to make sure that you select the correct QDF file to back up. Another way to do this is to invest in a backup program that will back up and restore your important data files on your computer.
You can also use the Windows image file and create an image file of your hard drive. If you have a problem with your hard drive the image file can be used to restore your entire computer system as it was the day you created this file. Most people have a subscription to Quicken if they are using this for work. In this case, just set it up to back up the QDF-BACKUP file to the cloud server or your Dropbox account. If you do a lot of entries each day it is a good idea to make a daily backup of this file.