When creating a report, it does not automatically add the extension (html, pdf, rtf) to the end of the report name when saving. The user has to make sure it is manually typed in when specifying the name and location of file to save to.
If a user overlooks this and does not specify the entension, the report saves but it cannot be opened.
WORKAROUND:
Manually type in the appropriate file extension when naming the report during its generation.
STATUS:
Issue fixed in version 5.0 of Toad Data Modeler. The latest version of Toad Data Modeler can be downloaded at: