Error "[DBNETLIB][ConnectionOpen(Connect()).] SQL server does not exist or access denied"

Musaib Pat 11 Reputation points
2021-03-24T08:22:41.22+00:00

Hi,

We are getting an error "[DBNETLIB][ConnectionOpen(Connect()).] SQL server does not exist or access denied" for few users on accessing ERP application and most of the users are able to access application without any issue. We have enabled TCP/IP and namepipes but still we are facing the same issue. I'm new to SQL.

Your help will be highly appreciated to resolve this issue.

Thanks in advance.

Regards,
Musaib

SQL Server | Other
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5 answers

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  1. Olaf Helper 47,516 Reputation points
    2021-03-24T09:16:26.83+00:00

    Is there may be a Firewall running on the client machine, blocking the access?
    => Configure a Windows Firewall for Database Engine Access

    Otherwise see MS Support: Solving Connectivity errors to SQL Server

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  2. AmeliaGu-MSFT 14,006 Reputation points Microsoft External Staff
    2021-03-25T06:14:42.143+00:00

    Hi MusaiPat-5515,

    Are you using the default instance? Are the instance listening on port 1433?
    If the SQL Server instance is a default instance and listen on port 1433, please ensure an exception is added to TCP port 1433 in the Windows firewall. If the default instance is listening on a non-standard port, Please refer to this article which might help.
    If the SQL Server instance is a named instance and listen on dynamic port, please make sure SQL browser service is indeed started and UDP port 1434 is not blocked on the firewall between the client and the server. If you cannot do either of them, you should switch your SQL Server instance to use a static port and add static port to firewall exclusion list.
    In addition, please check if there are incorrect alias on the client machine.

    Best Regards,
    Amelia


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  3. Michael Olivier 1 Reputation point
    2022-07-11T09:21:56.293+00:00

    Hi

    I have found a simple solution for the error on my side

    1. Check server and work station date and time. They should be the same.
    2. Check network modum and wifi router date and time. Should be same as Server and Workstation.

    If any of the network hardware or computers are out of sync with date and time sql will give [DBNETLIB] relatred errors

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  4. nunodevops 0 Reputation points
    2023-08-09T19:39:58.48+00:00

    Hi,

     

    To whom may concern, you should also verify your sql connection string for errors. For example if you have the server or instance name misspelled, the system gives you this error.

     

    Regards,

     

    Nuno

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  5. Ozgur Kovan 0 Reputation points
    2025-01-22T06:17:44.1833333+00:00

    It asked me if I would like to debug it , from there I was able to figure out that it was a wrong connection string in one of my local sites running in the IIS. I just stopped that website or I could've updated the correct db ip address.

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