He everyone, I have a Macbook running Snow Leopard, and I'm starting to find websites and Youtube won't play any more because my versions of Safari and Flash are old. I have enough RAM to upgrade to Yosemite, so I decided to try it out by installing on a USB drive. I have done that successfully, and quite like what I see. I can connect my printer OK, but I'm having trouble getting my Canon LIDE 70 scanner to work. According to what I read on the web (principally Jan Elgil and MacManus), Apple may not encourage Twain scanners any more, and the latest Canon driver for this scanner is for Mountain Lion. But these people say that I can still run the scanner if I install Twainbridge and use the Mountain Lion driver, and/or install some files to use the SANE protocol (which I don't really understand). I think I have tried everything they suggest, but the scanner, which runs fine in Snow Leopard, is not recognised by Yosemite - it doesn't show up in System profiler or VueScan or anything else. Can anyone here tell me please how to get this working (otherwise I may not be willing to upgrade to Yosemite)? Failing that, can anyone tell me what is required for Yosemite to recognise a scanner - what files in what locations? Thanks.