This tutorial does mention the FAT32 requirement:
Installing Windows 7 in native EFI mode from USB - bit-tech.net Forums
"That's it! No need to write boot sectors or anything like that - as long as you have a FAT32 filesystem with a \efi\boot\bootx64.efi file, the computer should pick that up and start booting."
However, I'm not sure what the fs:0 step is that you're talking about.
As an aside, there's no functional reason to move to GPT partitioning unless you're booting from a 2.2TB+ drive or planning to run more than 4 partitions.
the tech net tutorial mentions it, but I never found that one. the seven forums tutorial didn't even hint that UEFI may only like certain filesystems. I spent DAYS trying to install to finally discover that my EFI shell doesn't like UDF
the fs0: command moved me to the disk's directory. Without doing so typing the path to the efi file is useless
it's like typing A: into command prompt
It sounds like something went awry with your setup, then. But it's good to note for others who might encounter the same issue.
I thought I'd try installing Windows 7 in EFI mode again.
1. My Windows 7 disk does not have a efi/boot/bootx64.efi file. I looked and found that the efisys.bin archive contains the bootx64.efi, and that it must be extracted to a floppy drive.
2. I found an old floppy drive laying around, but my only floppy disk is dead.
3. I created a 80mb partition on my secondary drive and extrated bootx64.efi to it. the EFI shell successfully launched this, but it was unable to locate setup.
4. I created a 4gb partition on my second drive and extracted the contents of my Windows 7 installer disk to it, and placed the bootx64.efi file in the correct location. the EFI shell can find the file but it crashes once I press any key at the "press any key to install from disk" menu
I'm out of ideas. I'm currently downloading the official digital river ISO to see if it is already configured for EFI use.
How do I start the installer in EFI mode? thanks.
I followed these instructions: Installing Windows 7 in native EFI mode from USB - bit-tech.net Forums
I'm currently installing (had a false start because i upgraded my BIOS and forgot to set the SATA to AHCI mode), and I'm pretty sure it will work. it's definitely running and installing in GPT mode.
Too bad my motherboard doesn't support UEFI boot from DVDs though. I'll just make a hidden recovery partition on my second drive.
Most ISOs of Windows 7 or 8 (x64) don't have the EFI-compatible El Torito boot images... You'll have to make them yourselves, or use USB drive... For USB drives you'll find the tutorials on this site perfect... For using DVD, use oscdimg.exe to create a UEFI bootable ISO, for example, in How-To : Using Oscdimg.exe for Building W7.x, W8.x, WinPE Bootable DVD ISO Image
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