I'm not sure where this error originates, but having the Vista client completely freeze is a bad user experience.
I stumbled into this in SM Invoice [Preview] If the 'Custom Report' specified is currently open in the Crystal Reports Editor, and I hit the [Preview] button to pull and view the report.
I think users would appreciate an error message along the lines of "Error accessing report file. Perhaps it open in an editor?" instead of the entire Viewpoint Client freezing.
Nathan Sutherland
Dear Viewpoint Suggestion Box contributor;
We at Viewpoint sincerely thank you for your contribution to Suggestion Box on how we can improve Viewpoint products. While we can’t do everything at once, we rely upon your feedback to help guide the prioritization of our product improvements, and Suggestion Box is a critical tool for us to understand and prioritize our customers’ needs.
Viewpoint reviews Suggestion Box regularly for all of our products and updates statuses, adds comments, and performs various house-keeping (including deleting) as needed to ensure that Suggestion Box is maintained as a productive environment for product enhancements requests.
Not sure what behavior you're seeing. I've always gotten an error message when I have a report open in Crystal and then try to run it in Vista. Granted, the error is fairly worthless but cryptic enough that my users can't make any sense of it and contact me anyway. I've attached a screenshot of the error I get.