Problem

The NAV server failed to start, the event log said it cannot connect to database. However, when connect the database using SQL server management studio (SSMS), the database can be connected.

Solution

It maybe be possible that the DNS / domain server failed to connect / online

If possible, resume the DNS and domain server (110), the service should be automatic resume

If that's not possible, change the database setting in NAV server database setting to "localhost" (111) first

  1. Go to Dynamics NAV Server Administrator
  2. Select the NAV instance and find the database tab
  3. change the "Database" server to localhost （be sure you copy back the server string for future rollback）
  4. Start the server
  5. Also change for another server instance

Caution

The above setting will disable the ability for DB failover and it should use as temporary solution for urgent