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Dynamics 365 Community / Forums / Microsoft Dynamics NAV (Archived) / Installation error &qu...
Microsoft Dynamics NAV (Archived)

Installation error "The SQL Server instance '' exists, but a connection...."

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Posted on by Martinho Costa 779

Hello,

We are moving to azure our develpment structure. On NAV installation, in "specify parameters" step, I'm cleaning the "SQL Server Instance" field and when I click on "Apply" I get the following error: "The SQL Server instance '' exists, but a connection could not be established. Verify that SQL Server is running, that the TCP/IP protocol is enabled and, that a login exists for your Windows account."

I've tested the comunication between NAV machine and SQL machine and its up (installed SQL Management Studio on NAV machine and can load SQL server from SQL machine). The service user is administrator on NAV machine and also confirmed that TCP/IP protocol is active at SQL Configuration Manager.

Tried in NAV 2016 and NAV 2015.

Any idea? Thanks in advance

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  • Suggested answer
    keoma Profile Picture
    keoma 32,729 on at
    RE: Installation error "The SQL Server instance '' exists, but a connection...."

    has the service account the permission "log on as a service"?

    check your firewall settings, if the needed ports are added.

    check if the nav service account was added to the database as user with sql right db_owner.

  • Martinho Costa Profile Picture
    Martinho Costa 779 on at
    RE: Installation error "The SQL Server instance '' exists, but a connection...."

    Hi Jonathan.

    I've included the service account in "log on as a service" permission set.

    The firewall turnned off for same domain computers and also added the user on SQL with dbo rights.

  • Suggested answer
    keoma Profile Picture
    keoma 32,729 on at
    RE: Installation error "The SQL Server instance '' exists, but a connection...."

    is there a second nav service instance? if yes, check, if the service name and the ports are different.

  • Martinho Costa Profile Picture
    Martinho Costa 779 on at
    RE: Installation error "The SQL Server instance '' exists, but a connection...."

    That's the first nav service instance on the machine. Also tried to change the ports just in case.

  • keoma Profile Picture
    keoma 32,729 on at
    RE: Installation error "The SQL Server instance '' exists, but a connection...."

    please check the windows event log. maybe there are more details in the error message.

  • Martinho Costa Profile Picture
    Martinho Costa 779 on at
    RE: Installation error "The SQL Server instance '' exists, but a connection...."

    Somehow I'm not receiving the error message in the event viewer (Windows Logs/Application). Got quite confused now. Is it because it comes from a setup process?

  • Suggested answer
    keoma Profile Picture
    keoma 32,729 on at
    RE: Installation error "The SQL Server instance '' exists, but a connection...."

    means that error message comes directly from nav setup.

    best you run nav setup with demo profile and change the settings after successfully run with nav service management tool.

  • Verified answer
    Martinho Costa Profile Picture
    Martinho Costa 779 on at
    RE: Installation error "The SQL Server instance '' exists, but a connection...."

    Well, I did some changes... It works but I need to be honest I don't know why.

    Enabled "Named Pipes" on SQL Configuration Network. Instead of Custom Installation I did Developer. Have removed some features like "Install Demo Database" and some excel and outlook plugins.

    It's installing.

    Thanks a lot for your time Jonathan :)

  • Suggested answer
    keoma Profile Picture
    keoma 32,729 on at
    RE: Installation error "The SQL Server instance '' exists, but a connection...."

    the main changes, i think, were using a predefined setup mode instead of the custom, as i suggested, and enabling the "named pipes" protocol.

    quote: "For Microsoft Dynamics NAV to work correctly, the Named Pipes and TCP/IP protocols must be enabled for SQL Server."

    from msdn article "Troubleshooting: SQL Server Connection Problems":

    url: msdn.microsoft.com/.../dd983822(v=nav.80).aspx

  • Suggested answer
    Anton Modaresi Profile Picture
    Anton Modaresi 100 on at
    RE: Installation error "The SQL Server instance '' exists, but a connection...."

    I think you get this error because you have SQL server installed locally, while you're actually trying to connect to another SQL server.

    You need to run the SQL server component install on that machine, not the one where you install your other NAV software.

    If you did not have the SQL server installed locally, you would get a different error saying "SQL Server Instance '' could not be found"

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