That is interesting, you would think ASRock would make note of that situation in the manual.
I was thinking possibly it was related to the formatting of the floppy. Since the UEFI does not like extended partitions on a secondary internal or external hard drive during boot, maybe there is a correlation. My USB floppy seems to work fine.
All I might suggest is to disable the controller in device manager. Then reboot and re-enable it after rebooting to see if it might be picked up then. You may have to do a device search to find the controller, but since a floppy doesn't act like a USB device, it may not help. If it doesn't, boot without a floppy in the drive, if you have not already done so.
The UEFI Bios I have seen also have options during boot to allow Legacy/UEFI OpRoms. You might try changing any of those to the other option, and play with anything that mentions legacy enabled or disabled.
I appreciate all the questions and suggestions, but the fact is I purchased a motherboard with a floppy controller and a floppy disk cable connector. This is absolutely nothing in the literature and the user manual cautioning about the floppy disk drive not being detected on a Windows 7 x64 OS booting under UEFI on a NTFS formatted GPT disk.
The floppy disk is enabled in the UEFI BIOS or else I would not be able to boot from a MS-DOS disk. The floppy disk drive is recognized when booting Windows 7 x64 on a MBR disk under BIOS.
ASRock insists the problem is a Microsoft fault and Microsoft will not respond to any inquiries about the situation.