A paging file (aka: “page file” and “virtual memory”) enables the system to remove infrequently accessed modified data from physical memory to let the system use physical memory more efficiently for more frequently accessed data. Windows also uses the page file to store data when physical memory (RAM) is full.
Encrypting the page file prevents malicious users from reading data that has been paged to disk, but also adds processing overhead for filesystem operations.
This tutorial will show you how to enable or disable virtual memory paging file encryption in Windows 10 and Windows 11.