I have been getting an error message on my pc for a few days now that the twain.dll client thunking service is not working. From what I could find this is for scanners and digital cameras, neither of which i use anymore. I don't know whether the iphone would use this at all and I'm wondering if someone can tell me if I'd have problems if I delete the files. They are not listed in the programs list so I'd have to just delete from the windows folder in the c drive.