Problem solved We  had replaced the factory drive in the 7010 with an older one for use in testing. That older (2005 SATA) drive was the issue. I noticed it when I went to try to another drive just to rule it out. When the factory 7010 drive was placed back in the system those errors went away. Image was captured and restored.
I have an Optilex 7010 w latest BIOS which I need to use to build a base OS for Win10 Enterprise 64 (I don't have access to many newer PCs for this). Windows 10 installs fine and operates normally. 1st attempt: Installed DIA on the PC itself, used the Image Capture feature w/o Sysprep to attempt to capture maintenance image.  Operation proceeded fine until it rebooted. It then stopped at the loading Dell PE portion and eventually errored out indicating it could not find an OS drive (basic internal SATA drive). Subsequent reboots same result. Cannot get back into the OS at all now. I created a USB DIA drive using the environment I installed on the 7010 Win 10 build base before attempting to capture the maint image. So i rebooted with that USB drive, it booted into the DIA environment successfully however it also threw up an error at a later point that it could't located an OS drive. It would see my external drive fine in terms of a location to save an image but nothing for the system drive itself. Before I spend another day on this I want to know if I am doing something wrong or if this model will not work for this purpose? BIOS setting changes for this model?  I have used this on Win7 many, many times without issue now nothing seems to work without fighting every step of the way! 
Windows 10 Ent 64 Build Base: DIA unable to detect system drive for capture