We are handling of check boxes with the PDFviewer, but we found that for the attached PDF file, there is a check box with status cannot be altered by either the function Page_setAnnotCheckValue or Page_setAnnotRadio. The specific check box under the section "3. Collection Means" as marked in the attached image. We found that it returned false when calling Page_setAnnotCheckValue but true for Page_setAnnotRadio. We also tried to alter the status of the check box successfully with other PDF reader, e.g. Adobe Reader, please help to check the issue, thanks.