When I try to install Manjaro, it shows me a message saying "An EFI system partition is necessary to start Manjaro. To configure an EFI partition, go back and select or create a FAT32 filesystem with the esp flag enabled and mount point /boot/efi."

I have Windows 10 installed, and I'd like to not lose any data. Just want to dual-boot it. I created an /ext4 and /swap paritions on a seperate HDD already. Windows 10 is on an SSD.

I'm not sure what to do :/ I'd like to be able to choose between Windows 10 and Manjaro when I start up my PC so I really don't want to screw anything up.

Thanks!

If you have Windows 10, you should already have an efi system partition. It's probably /dev/sda1. You can check this by running fdisk -l /dev/sda (that option is a lower-case "l" by the way, not a "1"). Then use the mount command to mount it on /boot/efi as instructed.

Thanks, I did that and it seemed to work. I was able to boot into Manjaro. But, now I have a big problem, I'm unable to get into the BIOS or Manjaro. Every time I press F11 to access it, my monitors turn off, I get a no signal message and I have to restart. I can get into Windows if I leave my PC for a few seconds.

I'm not sure how to fix that :/ I'm pretty sure I accessed the GRUB menu once, but now no matter what I do nothing happens.

I'd appreciate any help!

EDIT: I also tried changing the boot order in EasyUEFI but that didn't help.

Pre-installed windows 10 is almost alway UEFI. Did you verify that on windows under My Computer to see if you had an EFI/FAT32 partition?

Did you boot and install Manaro EFI or were you just able to boot the Manjaro installation DVD? If you did the install, it should have created a separate folder on the EFI partition and installed it's boot files there. You should be able to check this by booting the Manjaro DVD and mounting the EFI partition. I don't think your attempts to install Manjaro would affect the BIOS, you might check the various settings.

I was able to boot and install Manjaro from my thumb drive. I'm not able to do that now though, every time I try to boot the Manjaro USB it gives me a 'No signal' message on my monitors.

Ok, I somehow got into Manjaro again, I honestly don't know how. I just restarted my PC...

These are my partitions: http://imgur.com/a/51PRR

I'm now trying to restore GRUB. Hopefully that won't burn anything.