cannot play "highly compressed" (zipped) files directly. You must extract them to a full ISO or folder format before the system can recognize them. Performance Stability
are often smaller because they only contain the digital version of the game rather than a full disc image. Compress for Emulation : If you are playing on a PC using the RPCS3 emulator ps3+iso+games+highly+compressed+better
Some popular tools for playing PS3 ISO games include: cannot play "highly compressed" (zipped) files directly