|Probably some registry entries remaining - maybe some files too (although they usually matter less). There are various ways you could tackle it:- |
You might be able to find it in msconfig startup tab If so, untick it and it will stop it bothering you, although still being partly present.
I don't normally advocate registry cleaners due to the risk but you could run the one in CCleaner (free) and let it remove anything that is to do with the old scanner. I have more faith in the CCleaner registry cleaner feature than others.
Finally, probably better, would be to do system restore to a time just before you installed the old scnanner.
Please come back and let us know how you got on.