The WinSxS folder is known as the Windows component store directory. It is the repository for component files required for system installations, including security updates, hotfixes and service packs. These files may also have future updates, which causes the folder to grow and occupy a large disk space over time.
Users should not manually displace WinSxS and residing files in an attempt to address disk space issues, because this may cause Windows installations to fail. To safely trim down the size of the WinSxS folder, users should run Disk Cleanup, Task Scheduler and other system utilities. Each version of Windows has varying cleanup tools, some of which perform automatically to conserve disk space.