Network printer/scanner recognised in 11.10 but not 12.04

I have a network connected HP Photosmart C309A all-in-one printer/scanner (connects directly to the router)
Both scanner and printer (including their respective configurations) were recognised and automatically configured by both Ubuntu 10.04 and 11.10 (10.04 still recognises everything correctly: 11.10 has been replaced by 12.04 so cannot verify).

However with 12.04
- it did not configure the printer correctly (for example, did not recognise that it has a duplex paper handler) - I had to do that manually
- it still does not recognise the scanner at all

Any thoughts?
Peter