I have tried downloading the new SL printer updates 3 times. Each time it installs, it fails, saying it’s corrupted. (8.5 mb file)
This is the first problem ever with my imac. Previous printer updates installed fine.
Should I install a program like Onyx to correct problems or is there something easier I should try first?
— B Mueller
My guess is that there was a simple download error when you first downloaded the update. Every time you try again, it just uses the cached version of the file already downloaded. Look in ~/Library/Caches/com.apple.SoftwareUpdate/ and clear it out.
Otherwise, do you need the printer update? If not, then maybe skip it. I don't think it is an issue that will affect anything else.