Okay, so I think I've got a bit of a mess here.  After initially trying to install Exchange 2013 RTM, (and set up a DAG), on two Windows 2012 (VMware) servers, I then attempted to install CU9, (which failed),From there, I ended up getting things to the point that I decided that since this is a new production Exchange environment, (all email data still on current Exchange 2007 Server,) I'd just scrap the whole thing and start over from the ground up.

I had everything ready to go again and I just decided to install CU9 right out of the gate, (which is probably what I should have done the first time).  I received an error that Exchange was in an inconsistent state and that I would need to install using the recovery mode:

"Error: Setup previously failed while performing the action "DisasterRecovery". You can't resume stup by performing the action "Install"."

From there, I open a cmd prompt "with admin" and run Setup.exe /Mode:RecoverServer /IAcceptExchangeServerLicenseTerms

This also failed.  Among the errors in the log file was "An error ocurred while setting shared config DC. Error: The call to Microsoft Exchange Active Directory Topology service on server 'TopologyClientTcpEndpoint (localhost)' returned an error. Error details Active Directory server  is not available. Error message: Active directory response: The supplied credential is invalid.."

It's now to the point that I can't even "uninstall" this failed installation of Exchange 2013 CU9.  I now get "Error: Setup previously failed while performing the action "DisasterRecovery". You can't resume setup by performing the action "Uninstall"."

I'd like to try to not have to start all over with my VM's, (because, to be honest, I don't think I'll get a clean install even after doing this.  I suspect there's something in my AD that's "leftover" from the previous setup.  I made everything the same with my new VM's, (Names, disk, memory, CPU, etc...)

Thinking I may need to open a case with MS on this one.  Any ideas?

• Edited by timahh2 Friday, July 31, 2015 7:06 PM

Wow, amazingly, (to me anyway, as I thought for sure I was going to have to open a case with MS), after some more research and persaverance, I managed to figure this out.  As I had thought, (but didn't know what entries I needed to remove), I had to do some specific removal of entries within ADSI.  I pretty much just manually searched and got lucky on this one.

ADSI Entries:

CN=Configuration, CN=Services, CN=<DomainName>, CN=Administrative Groups, CN=Exchange Administrative Group (FYIDIBOHF23SPDLT), CN=Database Availability Groups:  This is where my original install Virtual Node\DAG Name was located.

CN=Configuration, CN=Services, CN=<DomainName>, CN=Administrative Groups, CN=Exchange Administrative Group (FYIDIBOHF23SPDLT), CN=Databases:  This is where an entry of one of my databases was still showing up from my original 2013 install.

CN=Configuration, CN=Services, CN=<DomainName>, CN=Administrative Groups, CN=Exchange Administrative Group (FYIDIBOHF23SPDLT), CN=Servers: This is where one of the Exchange 2013 Nodes was still located from my original install.

Also, (within ADSI), I deleted the Exchange 2013 system user entries that I found in several articles, but referenced in my previous thread, under: Default naming context, DC=<Domain Name>, CN=Users:

DiscoverySearchMailbox{GUID}, FederatedEmail{GUID}, Migration{GUID}, SystemMailbox{GUID}, and HealthMailbox{GUID}

http://blog.dargel.at/2012/11/20/complete-remove-exchange-2013-using-adsiedit/

After doing all of this, along with having all my pre-req's in order, I ran the following 3 commands:

Setup.exe /PrepareSchema /IAcceptExchangeServerLicenseTerms
Setup.exe /PrepareAD /IAcceptExchangeServerLicenseTerms
Setup.exe (Right click and "Run as Administrator")

...and voila, Exchange 2013 CU9 installed without any errors. 

It's now on to Node 2, then DAG setup, and hopefully a successful migration. 

Thanks all.

• Marked as answer by timahh2 Friday, July 31, 2015 6:11 PM