CR prints no record although there is records in dbase

Dear all,

I found a problem and this makes me frustrated.
I'm using VB6 and CR 8, When I saved a transaction and print invoice, there is no data printed on CR (I'm sure the there is a record saved in database). The big matter is it's happened sometimes.
It runs ok for several transaction and happen again.
I'm really confused, I've tried to close all connection before printing invoice. But it still happened.
Please let me know what should I do.
Urgent..

Thank you.One thing that gave good result to me, was :
In VB6, before process the report:
Close the tables and database & execute DoEvents
ReOpen the database and tables (if needed) after preview or print the report