I figured out the problem.
I set up a public property of a class module that will be set to null once it is retrieved. In the format event, the value of the property is retrieved and the reprot runs OK. However, when the report is printed, somehow the Access report has to run the format event again so it only gets a null value.
I can understand that the code will not run correctly (so nothing is outputed) because of the null value. But, strangely there is no warning or error message at all.
The way I fixed it is to store the value of the public property to a report level variable at the Report_Open event. In the format event, the report level variable, instead of the public property, is retrived.
Seaport