The issue being discussed in this article is:
When you print a customized report, blank pages print between real pages. You may have also noticed a red line down the right side of your report in the Report Viewer.
The following is the cause:
This is caused when your report canvas is larger than the paper size minus the margins.
The following is the resolution:
1/ Open your report in the Standard Report Designer and click File > Edit DTools Report Information.
2/ Click Next and verify your paper size and margins.
In the example below, it is set to "Letter," which is 8.5" wide, and the left and right margins are .3" each. This means the maximum size for my report canvas is 7.9".
3/ Once you've verified, click Finish.
4/ In the Designer, click the gray area next to your report and verify the PrintWidth value in the Properties window.
In this example, my PrintWidth is 8.1" vs. the maximum of 7.9", which is causing the issue.
5/ Change this value and then publish your report.
If you cannot resolve this issue, please open a Support Ticket.