One of the safest ways to how to delete pagefile. sys is by going through Windows advanced system settings. You need to open System Properties, find Performance Settings, and then get to the Virtual Memory section. Turn off automatic paging management, pick the drive that has the pagefile, and hit “No paging file. ” Once you restart your computer, Windows will delete the file for you. But, totally turning off virtual memory may result in slow performance, system crashes, or memory errors when running demanding applications. A machine with a large quantity of RAM can tolerate a decrease in the use of paging memory, but generally it is a good idea to keep some virtual memory for ensuring system stability and clean multitasking performance.