Error: add_fileset_file: No such file C:/intelFPGA/20.1std/ip/altera/altera_nios2_gen2_rtl/cadence/altera_nios2_gen2_rtl_module.sv

Due to a problem in the Intel® Quartus® Prime Standard Edition Software v19.1, 20.1, and 20.1.1 for Windows operating system, you may see the above error message when you generate the RTL of a Platform Designer system that includes a Nios® II processor IP.

A patch is available to fix this problem in the Intel® Quartus® Prime Standard Edition Software v20.1.1, upgrade your design to this version for patch compatibility.

After upgrading your design, download and install Patch 0.01std from the following links:

• Intel® Quartus® Prime Standard Edition 20.1.1 Patch 1.01std for Windows (.exe)
• Readme for Intel® Quartus® Prime Standard Edition 20.1.1 Patch 1.01std (.txt)

This problem is fixed starting with the Intel® Quartus® Prime Standard Edition Software v21.1.