Ok. Let's hope that i will be able to boot the laptop after deletion.
"Formerly, on disks formatted using the older MBR partition layout, certain software components used hidden sectors of the disk for data storage purposes. One example of this is the Logical Disk Manager (LDM), which, should the disk be converted from a basic disk to a dynamic disk, would store metadata in a 1 MB area at the end of the disk which was not allocated to any partition.
GPT formatted disks and the UEFI partition specification do not allow hidden sectors. Microsoft reserves a chunk of disk space using this MSR partition type, to provide an alternative data storage space for such software components which previously may have used hidden sectors on MBR formatted disks. Such software components, for example LDM as mentioned above, can create a small software-component specific partition from a portion of the space reserved in the MSR partition"
"It's a placeholder invented by Microsoft. It doesn't contain any meaningful data and it's there just in case you'd ever need to create some additional partition for special uses. In that case, Windows will shrink the Reserved partition and create a new one in the recovered place. Deleting it shouldn't do any harm now, but you may face some problems in the future."
"Now, before you delete any of these, you should ask yourself a question: "why would I do that?"The free disk space you gain probably isn't worth it. Your hard drive has 700 GB of usable disk space. Those two partitions take up less than 400 MB combined. That's 0,05714% of your hard drive. You'll recover just a little piece of the disk, while risking boot failure and possible problems with Windows in the future."
What the future holds you never know.
In this case, I would have only made an attempt to find the root cause for the MSR partition getting a drive letter and remove the cause and let it be till such time, instead of going against the basic tenets and purpose for which Microsoft has created it.
Possible actions one could take::
- restore the system to a previous point in time with System Restore
- restore the system with a previous backup
- query Microsoft Support on the issue
- query HP Technical Support on the issue.
I am putting this on record here lest people take deleting the MSR partition is the right solution - far from it.