Tourless,

My Apologies! I have deleted my post. Disregard the information I posted. Guess I need my glasses updated. Follow the information ejn63 posted.

It should be possible, but it's not something Dell (or Intel) supports.  You'll need to build a custom Windows 7 image with the USB 3 drivers slipped into it.  While it can be done, the process is not a trivial undertaking.

Start here:

https://www.intel.com/content/www/us/en/support/articles/000017241/mini-pcs.html

Unfortunately I'm not working with an Optiplex 3050, I'm working with an Inspiron 3050.  But I will check the processor.

Thanks, enj63.  I appreciate the starting point, and although I was aware and tried the Intel tool, I was not working with a GPT partition scheme.  I rebuilt my USB and added the USB 3 drivers but still get a Blue Screen with a stop error 0x000000A5.  The message is always the same... "The bios in this system is not fully ACPI compliant.  Please contact your vendor for an updated bios."  The funny thing is the Inspiron 3050 is not on the list of affected systems according to http://www.dell.com/support/article/us/en/04/sln300564/dell-systems-with-the-intel-skylake-or-braswell-chipset-lack-usb-20-support-and-will-not-boot-to-dell-windows-7-media?lang=en. There are actually 3 USB 2 ports and only 1 USB 3.  I have tried using a USB 2 drive on the USB 2 ports and end up in the same position, blue screened.

I've tried various partition schemes when creating my installer USB, tried various bios configurations including ATA v. AHCI, changing boot options in the bios to UEFI without and without secure boot, Legacy, and Legacy Option Rom, and nothing.  I get blue screened with the same stop error, same message.

Did you start your media build with a copy of Windows 7 including SP1 and post-SP1 updates?

I've got an SP1 but not post SP1 updates.  For that I'll need a link and hopefully some instructions to integrate the post SP1 updates into the installer.

As a side note I don't seem to get as far along in the install process as others have posted.  I get the Windows Loading progress bar, then the initial Windows splash screen but it halts and Blue Screens on me just before it starts loading the animated logo.

See here (most folk will install Windows 10 as it's far more hassle than it's worth to create Windows 7 up to date installation media):

https://www.youtube.com/watch?v=cVo20Tx-0_M

http://dellwindowsreinstallationguide.com/slipstream-win7/

Thanks Doc, but no good.

I've built a number of these customer installers with USB 3 drivers and have run the gambit of USB formatting options and bios settings and have yet to find the right combination.  At this point I'm fairly convinced that you simply can't install Windows 7 Pro on an Inspiron 3050.

Come on people, somebody prove me wrong... I dare you! :)