Problem When scanning with an Opticbook 3600 using ReadIris on a Mac, you get an error stating that it cannot find the BookTWAIN device. Cause This can be caused by a bad driver or installation. Solution Turn off the scanner. Delete these folders: /Library/Application Support/Plustek /Applications/Plustek Delete ths folder: /Library/Image Capture/TWAIN Data Sources/BookTWAIN.ds Delete all… Continue reading "Cannot find BookTWAIN" with OpticBook 3600