Q: When booting my iMac 27" Retina 5K device to install Windows 7 the kb and mouse are unresponsive in the Windows install screens.  The boot device is a USB 2 flash drive.

The flash drive is a USB2 device.

There was an external HD but I removed it. the only USB device is the BCA created flash drive (USB2).

When booting with the Option key held:

I select Windows drive

A banner at the top says booting from BCA created device

A bar appears at the bottom saying Loading Windows files

A Starting Windows screen shows with the Windows logo

A blue screen with no text appears

An Install Windows screen appears with options to select language, keyboard, etc., and click next to continue.

     I cannot get past this screen as kb and mouse don't work.  I tried a USB keyboard and it also was unresponsive

OK  I ran both procedures and tried the windows install after each one.  No change.

Here is the report on the USB drive.  How do I confirm that it is USB2?

Cruzer:

  Product ID:    0x5530

  Vendor ID:    0x0781  (SanDisk Corporation)

  Version:    2.01

  Serial Number:    2005244463141892A628

  Speed:    Up to 480 Mb/sec

  Manufacturer:    SanDisk

  Location ID:    0x14500000 / 1

  Current Available (mA):    500

  Current Required (mA):    200

  Capacity:    32.02 GB (32,015,679,488 bytes)

  Removable Media:    Yes

  Detachable Drive:    Yes

  BSD Name:    disk3

  Partition Map Type:    MBR (Master Boot Record)

  S.M.A.R.T. status:    Not Supported

  Volumes:

WININSTALL:

  Capacity:    32.02 GB (32,015,678,464 bytes)

  Available:    27.66 GB (27,657,011,200 bytes)

  Writable:    Yes

  File System:    MS-DOS FAT32

  BSD Name:    disk3s1

  Mount Point:    /Volumes/WININSTALL

  Content:    DOS_FAT_32

  Volume UUID:    A27DB612-3BF1-36B2-AED1-0F08C0F1F394

My first attempt was with a Sandisk Cruzer Fit which is a new 16Gb drive and the packaging bills it as a USB2.0  (I just tried again with that drive - no change)

I do not have a wired Apple KB or mouse although I tried a USB keyboard which the IMac recognized but Windows didn't.

I had an iPhone 4s in my pocket with Bluetooth on but it doesn't interfere with normal iMac operation.

Maybe I will go back to square 1 with Boot Camp and recreate the boot file from the Windows DVD.  The version of BCA is 5.1.4   Is that the latest?

Yes, I have a Windows DVD and I just recreated the .iso file and Windows Installer using Boot Camp Asst.

The optical drive is an Apple USB 2.0 Superdrive

Yes, my version of BCA is 5.1.4 (500)

I tried the newly created Installer on the Sandisk Cruzer 16Gb flashdrive.  No difference.

Is there a way to initiate the Windows Installation other than booting with the option/alt key and selecting Windows?  The very first time it was initiated from BCA and the KB worked in the problem screen, but when I got to the screen where I select the partition to install to I couldn't find the BOOTCAMP partition and I bailed out and shut down.  (the BOOTCAMP partition shows that it exists now in Disk Utility but now I cannot get to the screen to select and format it)

I removed the BOOTCAMP partition, recreated it and was able to successfully install Windows 7.  The mouse didn't work but the keyboard did.  The initial screens were somewhat different than booting straight from the Install drive.

Windows on the iMac looks better than it ever did on my old PC.

Do I need to keep the flash drive in place or will Windows boot from the BOOTCAMP partition?

Thank you very much for your patience and assistance.  I am fairly new to the Mac world and still learning.

Bill