Prelogin packet SQL 2014 SP3 CU2

• jayoub

  SSCertifiable

  Points: 6990

  More actions

  March 15, 2019 at 7:35 pm

  #409703

  I hope someone can help me with this.  I am getting the below error my SQL Error log:
  The prelogin packet used to open the connection is structurally invalid; the connection has been closed. Please contact the vendor of the client library [Server IP]
  Error: 17828, Severity: 20, State: 3.

  I am running SQL Server 2014 SP3 CU2 on Windows Server 2012.  The source of the failed login is an application server running Windows Server 2012.  The application is working fine and in the SQL error log there are one or two successful logins and the failed logins are happening every few minutes.  All the articles that I am reading say this problem was eradicated may years ago or they suggest increasing the maxtokensize in the registry

  I have seen this problem before on the server and usually a reboot of the application server resolve the problem, but not this time.   

  Any thoughts on why I am getting this would be helpful

  Jeff