Please keep in mind, once you purchase your product you will receive a unique one time link to download it. Each link is only good for 24 hours . Please make sure you open it on the device you need it. All our files are in pdf form which means you need Adobe to access them. Head over here to make sure you have the latest update. I recommend not installing the extras that come with Adobe- just Adobe itself. Most products in the Market are zip files (compressed). This means you need to unzip it before you access the file. If you don't unzip it, you'll get an error message. To read more about how to unzip a file, please see this site.