Acrobat printing on win98

Hi all,
I print a document in Acrobat5.0 use my own printer driver, when I push the print button and print it first time, Acrobat show an error dialog, but when I push it and print again , acrobat print normally. I traced my driver source code, but I can’t find anything unexcepted. Can anyone tell me what wrong with my driver?

Best Regards

hcheng_qi