Trouble scanning negatives

[Antonio Bunt]

Hello, I scan negatives using an HP ScanJet G4050, the problem is that lately, the images I scan appear squeezed like a bad CinemaScope transfer and with part of the adapter (a white line under or at the side of the negative) when opened in Photoshop. Is it a software problem? My scanner needs calibration? The weird thing is that positives come perfect. I know this is not a dedicated negative scanner but it used to work fine. Any tips and help will be appreciated, I have a deadline! Thanks!