In this article we’ll show how to manually repair accidentally deleted Windows boot partition on UEFI system. Initially, the article described my experience with restoring the boot EFI partition on Windows 7, but the article is also relevant for modern Microsoft operating systems (from Windows 7 to Windows 10). This article often helped me after accidentally formatting or deleting the EFI partition on Windows 10. I’ll show you an easy way to manually rebuild the boot EFI and MSR partitions on Windows.

1. Gparted Create Efi Partition

Contents:. GPT Partition Structure Consider how the partition table on the bootable hard disk with GUID partition table (GPT) on the system should look like. You should have at least the following partitions:. EFI System Partition or ESP (Extensible Firmware Interface) — 100 MB (partition type — EFI). Microsoft Reserved partition — 128 MB (partition type — MSR). Primary Windows partition (the partition containing Windows). This is the minimum configuration.

These partitions are created by the Windows Installer when you install the system on an unformatted disk. Computer manufacturers or users can create their own partitions containing, for example, Windows Recovery Environment in the winre.wim file, a partition with the system image backup provided by the manufacturer (allows to roll back to the default state of the system), user partitions, etc. The EFI partition with the FAT32 file system is a mandatory partition on GPT disks on UEFI systems. This partition, similar to the System Reserved partition on drives with MFT partition table, stores the boot configuration store (BCD) and a number of files needed for Windows boot. When the computer boots, the UEFI environment loads the bootloader (EFI Microsoft Boot bootmgfw.efi) from the EFI (ESP) partition and transfers control to it. If this partition is deleted, Windows can’t boot correctly. The MSR partition on the GPT disk is used to simplify partition management and is used for service operations (for example, when converting a disk from simple to dynamic).

The EFI partition is initially blank and not used for booting. However, the EFI partition is used as a staging area for firmware updates. Apples's Software Update. Thus, you might consider shrinking some other partition from its end and create a new FAT partition in the freed space. This should give you space to hold the file(s) you need. In theory, you should be able to store the boot.wim file on an HFS+ partition, since Apple's EFI can read HFS+ just as well as it can read FAT.

This is a backup partition that does not have a partition code assigned. This partition can’t store user data.

In Windows 10, the size of the MSR partition is only 16 MB (in Windows 8.1 the size of the MSR partition is 128 MB), the file system is NTFS. After a few days of frustration, I’m happy to say this guide finally resolved the issue. I had 2 UEFI partitions, 4 recovery partitions, and then 2 partitions for my OSes (Win10 and Ubuntu).

After messing around with getting rid of grub and returning the partition space back to windows, I ended up screwing up my entire boot. And after about 2 days of scouring the internet and trying all solutions available, this is thankfully the first one that got me back to a usable system. Great thanks to the writer(s) of this article for getting me out of a bind. A big thank you! Your write-up saved me this weekend. HP Workstation Z440, shrank windows partition and tried with Acronis True Image (comes free with new SSD Crucial MX300) to clone HDD to SSD. But upon reboot nothing, no OS can be found.

Gparted Create Efi Partition

Your method saved me. If the windows partition does not extend to the end, then upon remaking EFI and MSR partitions, they are placed after the windows partition which I am not sure if it would work. One has to add the OFFSET flag to create partition. For MSR the offset should be 101.1024 = 103424. Hope this is helpful to someone else Reply.