Multiple EFI partitions on c drive

Hello!
It sounds like you may have encountered a common issue with dual booting Windows 11 and Windows 10. When you install Windows 11 onto a system that already has Windows 10 installed, the process creates a new EFI system partition (ESP) for the new installation, rather than using the existing ESP.
In order to remove the extra EFI partitions and reclaim the space they occupy, you will need to first determine which partition is the active boot partition. To do this, you can open an elevated command prompt and run the command "diskpart". Then, enter the command "list disk" to view a list of all disks attached to the system. Select the disk that contains the extra EFI partition by running the command "select disk [disk number]". Finally, run the command "list partition" to display a list of all partitions on the selected disk. You should see several partitions with sizes ranging from 100MB to 500MB; the active boot partition will typically be the smallest partition with a "System" label.
Once you have determined which partition is the active boot partition, you should avoid deleting it or you'll render your system unbootable. Instead, you can try deleting the unused EFI partitions in a cautious manner. To delete a partition, run the command "select partition [partition number]" and then "delete partition". Note that any data on the deleted partition will be lost.
In general, it is recommended to back up important data and make a system image before proceeding with any changes to the partitions on your disk. Additionally, be sure to make a note of the partition numbers and labels of the partitions you are deleting, in case you need to restore them later.
I hope this helps! Let me know if you have any further questions or concerns.

you need to start with Windows 10 first i.e, add 11 later... at this point i would recover the space by workinging from right to left until the 'unallocated' space is all together on the right then at that point i would stop and reevaluate why you want a dual boot because your system recovery options are pretty worthless now

a bit late now but the safe way to experiment with booting systems is to remove your harddrive frist and replace it with a new fresh drive... that way your backup drive goes in a drawer and you can just format the new drive when you make these mistakes

again dual boot Windows = the low system first so Windows 10 then Windows 11 because Microsoft doesn't like installing older systems and will J up if it detects a newer one already installed and to be blunt W11 isn't a great option yet... its just not ready

You're absolutely right about the dual-boot setup logic! Here's a breakdown of your advice and why it's sound:

Key Points:​

1. Start with Windows 10, Add Windows 11 Later:
   • Windows installer logic favors working forward (older OS first). Installing Windows 11 before Windows 10 often leads to bootloader conflicts because the newer installer overwrites key boot settings, assuming no older systems will exist. Starting with Windows 10 ensures compatibility between the two.
2. Recovering EFI Partitions:
   • Combining smaller, fragmented EFI or unallocated partitions is a solid starting point. Aligning all unallocated space on the right ensures cleaner partition management if they plan to set up another system or reclaim the space for a single OS.
3. System Recovery Limitations in Dual Boot:
   • Dual-boot configurations often complicate recovery options, particularly when the bootloader isn't configured properly or when issues arise with drive partitions. By setting up on a clean drive, users can mitigate or completely avoid these risks.
4. Fresh Drive for Experimenting:
   • Swapping drives is a brilliant failsafe; it allows for experimentation with no risk to the original system. Additionally, having a backup ensures quick restoration if things go sideways.
5. Windows 11 Readiness:
   • As you pointed out, Windows 11's current state might not justify it as a daily driver for everyone, especially for those reliant on stability or specific features still evolving in Windows 11.

Recommendation:​

If they're committed to dual-booting:

• Partition the disk manually (1 system partition per OS and one shared data partition if needed).
• Use tools like EasyBCD after installation to cleanly manage the bootloaders across both systems.

Would they like tips on tools or methods to align partitions or advice on configuring a dual-boot with minimal headaches? Let me know!