The following link will take you to the initial download page for your CanoScan LiDE100
http://www.usa.canon.com/cusa/support/consumer/scanners/canoscan_series/canoscan_lide100#DriversAndSoftware
Once on the download page, use the Select OS drop-down menu to select the operating system of the computer on which you will be installing the software. You should then select the desired download from the list of Drivers or Software files. Next, you will need to agree to the terms of the Disclaimer message (towards the bottom of the page) to continue with the download process. After clicking the I Agree – Begin Download button, follow the instructions to download and install the driver. The time for the download process may vary depending on the speed of your Internet connection and the size of the file.
To use:
1. Plug the scanner’s USB cable into your laptop.
2. Place material to be scanned facing down on the document glass.
3. Start the MP Navigator EX program. If you can’t find it, open up your Applications folder and then open up the Canon Utilities folder and double click on MP Navigator EX.
4. On the scanner, click the scan button located on the front of the machine and away you go!