A Microsoft Reserved Partition (MSR) is a partition of a data storage device, which is created to reserve a portion of disk space for possible subsequent use by a Windows operating system installed on a separate partition. The System Reserved partition consumes 100 MB of space on Windows 7, 350 MB of space on Windows 8, and 500 MB of space on Windows 10. The Microsoft Reserved Partition (MSR) is only used on the UEFI systems using GPT partition structure. txt, and other files that are needed to boot the system, such as drivers. Don't worry, I've solved it easily here without the help of another running computer.