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InvalidCastException: Can not convert object type '.' to '.'


I have attached the screenshot of the error.

Document sample sent via email. I have detected that the error described above occurs when you navigate to page 87.

Thank you.

Alexis Rosano


Hello Alexis,

Sorry for the delay. Thanks for providing the file “2941_1.pdf”, we have checked it and were able to reproduce the issue that you’ve reported. Our developers will start to work on it, ticket is attached to the forum thread. By the way, we also found out that it works good in the HTML-based mode - you can use this mode in conjunction with this particular document as a temporary solution.

Sorry for the inconvenience.


The issues you have found earlier (filed as WEB-1653) have been fixed in this update.

This message was posted using Notification2Forum from Downloads module by GroupDocs Notifier.


Hello Denis, thanks for your answer.

The first screenshot was with the HTML based mode.

Now, I have attached the screenshot with the Image based mode (translation: Index was out of range. Must be non-negative and less than the size of the collection.
Parameter name: index)


Hello Alexis,

The “ArgumentOutOfRange” exception - it is exactly the same exception that we’ve obtained when trying to display a “2941_1.pdf” in image-based mode. About HTML-mode - we double checked this, and yes, we were able to reproduce the same “InvalidCastException” exception, but not on the page #87, but on #88. We’ve added this bug to the Jira and attached a ticket to this forum thread.

Thanks for pointing us on this.