HP Printer & Drivers

I have a HP laserjet 4350dtn, we are trying to print a legal size scanned image that is stored in a prgram (Access I guess, another vendoer). This program was printing out the legal size documents find until we changed the printer. We tried all the HP print drivers. There is anothe laserjet 4350 in the office and its set up to print legal size paper and the legal size document print fine there. Any suggestions?