Sql-server – The Target Principal Name Is Incorrect. Cannot Generate SSPI Context (SQL or AD Issue)

I don't know anything about Remote Debugging, but you can use Windows Authentication between two computers on different domains or with no domain, if they have an identical user account with the same password.

1. On the client machine, create a Windows account UserSQL, with password test123
2. On the server, create a windows account UserSQL, with password test123
3. On the server in SSMS, add UserSQL to the sysadmin role
4. On the client, run SSMS as UserSQL and connect to the server using Windows Authentication.

One other question. When you connect to the SQL Server instance from the client computer, are you using an IP address or the name of the Instance? I'm not sure if this is true or not, but whenever I have used Windows Authentification to connect to SQL Server, I use the instance name. If that is not possible because they are on two different networks, then you would have to setup an alias on the client machine in SQL Server configuration manager to associate the IP address with the distant sql server.

--edit

I just had some additional thoughts after reading a similar article in Microsoft's forums

http://social.msdn.microsoft.com/forums/en-US/sqlnetfx/thread/840841cc-ae4a-45fc-b1ab-0708dc4403c0/

Is there an external firewall between the two computers? From the client, can you do a telnet to each one of the ports from the command line

I.E. from the dos cmd prompt you type

telnet serveripaddress 139

telnet serveripaddress 445

Is the user that you're using to connect to the server instance in the sysadmin role? Can you debug locally?

The points you have listed are shown in BOL here, and even though it quotes:

SQL Server Setup will not block installation on a computer that is a domain controller

It states on this KB article that the setup will fail, although the applies to only list up to 2012 version.

One main reason you are going to have against doing this is Microsoft Support. As it states in documentation you should not install it, they are not likely going to provide support. Especially if you experience any security or performance issues. Unless you fork over a good bit of money they are probably not going to do much for you.

I have never seen a company put these two roles together out of choice. I hate to say it but if they need to run an application in SQL Server and it is going to be a mission critical application there is no reason for them not to invest in running that application. Hardware is cheap these days and it does not take much for AD to run if your organization is that small. You could even go and get 2 or 3 year old hardware for that matter.

Now with that said, Window Small Business server used to be the one stop shop for a situation like you describe. It is an AD, Exchange, and web server all on in one; and if I recall also had an installation of SQL Server but I can't remember. I setup one of these servers for a department one time.

However with Window Server 2012 they changed this to Window Server Essential Edition, and I am not sure what roles you get with this Edition. I would suggest though you simply spend the money to get Standard Edition. A feature you get with Standard is licensing to run two guest OS virtual machines via Hyper-V. If you size the hardware appropriately it will allow you to run your SQL Server instance in one VM and then your application in the second VM. Although your performance is all on one server it provides a boundary separation and would be a fully supported setup by Microsoft. Just my two cents.