You may be exposed to a vulnerability issue if you have installed or plan to install Quartus prime/Quartus II software from v11.0 to v18.0 to a location with space(s) in the path. See this KDB solution for more details.
Download large, standalone installation files to manually install complete software and device support.
Note: If you download and install only the QuartusÂ® II software, subsequently you must also download and install the device support . You do not have to install all the device support files. You can install only the device support files that you need.
Use a DVD image to create your own installation DVD to install Altera software and device support if you do not have consistent internet access or you require a DVD. You download one large file and use it to create an installation DVD.
Disk space: A full installation of the Altera Complete Design Suite v12.1 requires approximately 10 GB of available disk space on the drive or partition where you are installing the software, and approximately 30 MB of available space on the drive that contains your TEMP directory (Windows only).
View the following documentation for Quartus II software and device support details:
Software support: The Quartus II Software Support page can help with questions or problems that are not answered by the information provided here or in Quartus II Help. You can also contact Altera application engineers for assistance through the mySupport site.