Version 9.0

You no longer can. Except for 13.0sp1/13.1, the earliest version of Quartus available is 17.0.

Intel/Altera removed all earlier versions from online access back in 2020 IIRC.

If you can be explicit about which device and/or family you need support for that will allow for a much better answer.

Intel recommend to use the latest supported Quartus version for the device family used. Quartus v9.0 is definitely been discontinued.

If you do not find the desired Quartus version in the Intel Software Download Center, it is usually indicate that the software has been discontinued and you cant download it anymore.

Intel Software Download Center:

https://www.intel.com/content/www/us/en/collections/products/fpga/software/downloads.html?s=Newest

Use the left-hand filter pane to refine the search results. Example click the desired device family to get the list of the latest supported Quartus version.

I believe I have answered your question. With that, I will now transition this thread to community support. If you have a new question, feel free to open a new thread to get the support from Intel experts. Otherwise, the community users will continue to help you on this thread. Thank you.

Best Regards,

Richard Tan

p/s: If any answer from the community or Intel support are helpful, please feel free to give Kudos and select the best solution.