Short description of System Cleaner 5.91c: System Cleaner is the fastest and easiest way to restore your PC's performance, cure random crashing, boost boot-up and shut-down times, and free up wasted disk space at the same time. System Cleaner also protects your PC against registry failure and data loss caused by improper settings, registry corruption and other common Windows-related problems. System Cleaner is quick and easy and it protects your online privacy too.