Not able to print over VPN

I have Crystal Enterprise servers installed in one machine and a java
web application deployed in Tomcat to interact with the Crystal
Management Server. I have two printers one in the same local network
shared and the other in a different location connected through VPN.
I have my own application which issues a print command and prepares a
URL to access the web application. The web application gets the
printer network address as part of the URL that it recieves from my
own application.

When I give the network address of the local printer it prints
successfully but when I try printing with the printer over VPN it
fails.

In the History tab of that report in CE it gives the error message
"Error Message: Request cancelled by the user. File C:\Program Files
\Crystal Decisions\Enterprise 10\Data\procSched
\lthcbackup.reportjobserver\~ce10f04a4b6612802.rpt. "

This issue is critical to our project and I request everyone to help
me in this...

Thanks and Regards,
Abhijan

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