Hi, I'm Pete. Welcome to JustAnswer! I'm reviewing your question now, and will post back with your reply ASAP.
You should be using Canon Scanner Driver & Utilities V2.8.1 for Mac OSX 10.7.5
What version are you using?
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Ok, then it may be a permissions issue.
Try repairing the Disk Permissions on the Mac and let me know if that helps:
1. Close all applications.
2. On the Apple menu bar, click Go, click Applications and then click Utilities.
3. Double-click Disk Utility.
4. Highlight your hard drive/partition on the left.
5. Click Verify and then Repair Disk Permissions.
6. Restart the Mac.