Software that is under sustaining support will no longer be available for download. You need to follow Note 1071023.1 to open a NON technical SR requesting the software.
Please make sure the Windows OS is certified / supported or you will encounter issues installing or using Discoverer client software. See Note 233047.1 for certification matrix location and FAQs regarding certification.
Please note that Discoverer is at end of life. Therefore, it is important to maintain a stable Discoverer environment for as long as it takes to move to OBIEE or other replacement.
--- Notes of interest
Note 1071023.1 - How to Request Software When Unable to Access or Software is Unavailable on the Oracle Software Delivery Cloud
Note 1634827.1 - Oracle Business Intelligence Discoverer Statement of Direction - March 2014
Note 233047.1 - How To Find Oracle BI Discoverer 10g and 11g Certification Information