At some point, this system was upgraded to Windows 10, apparently with a wipe out of the original OS.  Since Windows 10 has been activated, the system has a digital entitlement - meaning you can download an image of the same version of 10 (10 or 10 Pro) and use it to recover the system.

There's no way to do a full factory recovery once that recovery partition is lost.

Open the disc manager (control panel - computer management - disc management).  Is the OEM recovery partition listed?

Sorry, I should have stated this this system was originally shipped with Windows 10 and has not been upgraded. The only thing done was a variety of driver updates, all from Dell, all recommended by Dell Support Assist. Nothing has happened that should have changed recovery means.

The system should have any OEM recovery partition intact.

Thanks for replying though.

Looks like the partition is there.  Try creating a set of recovery media for your system:

www.dell.com/.../SLN297924

(you'll need that anyway should the hard drive ever fail).

If you can successfully create the recovery media, you can use it to restore the system.

If not, you should see an error message that points to the problem.

Yes, and it's 11.35 Gb.

Thanks for the tips. I guess I can try to create a recovery drive and see if a possible error leads to an answer. I suppose this may not work if the factory reset option doesn't. Or maybe it will just create a standard recovery image that isn't factory at all - like on a clean installed system?

The following seems to indicate that creating a recovery drive will just create a standard WinRE image.

Reagentc points to partition 4.

Diskpart shows partition 4 is 902mb.

Thinking that creating a recovery drive will not provide joy.

I know I can download a Dell image to create a factory recovery. The issue is that this system is remote and I cannot get my hands on it or I would have already done that. The factory reset seemed the quickest and easiest way.

Factory settings are completely obsolete... Even if the system was shipped with "Windows 10" it will have upgraded to "Windows 10"....

Windows 10 has 3 mainstream builds so far Windows 10 RS1, Windows 10 TH2 and Windows 10 TH1. Your factory settings would have likely been Windows 10 TH1 or WIndows 10 TH2 and your system will have upgraded to Windows 10 RS1. 

The upgrade from TH1 to TH2, TH1 to RS1 or TH2 to RS1 is the equivalent of a full OS Upgrade install similar as Windows 8 to Windows 10 RS1 or Windows 7 to Windows 10 RS1.

Microsoft are updating Windows 10 installation media roughly every 3 months. Simply put Dell factory settings will always be obsolete... moreover OS Upgrades have the tendency to break the ability to use Dell Backup and Recovery.

Windows 10 RS1 - July 2016

Windows 10 TH2 (Update 2) - April 2016

Windows 10 TH2 (Update 1) - February 2015

Windows 10 TH2 -  November 2015 

Windows 10 TH1 - July 2015

You should download a Windows 10 RS1 .iso and use it for clean installation:

http://dellwindowsreinstallationguide.com/download-windows-10-oem-and-retail-iso/