“Index was out of range. Must be non-negative and less than the size of the collection. Parameter name: index.”
1. Figure out where this error was coming from was to delete individual items one at a time from the report and then try and preview it. Don’t forget to back up your report before you start deleting your stuff.
2. If you imported the reports from somewhere, the .rdl file may have been corrupted. You may have to go through your .rdl file using “Code View” and look carefully at text box properties and things like that. Pay special attention to the size and look for any negative values or zero’s. Also, be on the look out for text boxes with size attributes larger than their containing text box. This could also cause the above error.
3. A sub-report that is too large could also cause this error.
4. A page header or footer with an element like an image or text box that is too large could also be the culprit.
5. Some people have also had success correcting this problem by deleting the page header and/or page footer and recreating them, so you may want to try that.