Could not connect to the database

Exception
System.Data.SqlClient.SqlException (0x80131904): Connection Timeout Expired.  The timeout period elapsed while attempting to consume the pre-login handshake acknowledgement.  This could be because the pre-login handshake failed or the server was unable to respond back in time.  The duration spent while attempting to connect to this server was - [Pre-Login] initialization=5; handshake=14992;  ---> System.ComponentModel.Win32Exception (0x80004005): The wait operation timed out
   at System.Data.ProviderBase.DbConnectionPool.TryGetConnection(DbConnection owningObject, UInt32 waitForMultipleObjectsTimeout, Boolean allowCreate, Boolean onlyOneCheckConnection, DbConnectionOptions userOptions, DbConnectionInternal& connection)
   at System.Data.ProviderBase.DbConnectionPool.TryGetConnection(DbConnection owningObject, TaskCompletionSource`1 retry, DbConnectionOptions userOptions, DbConnectionInternal& connection)
   at System.Data.ProviderBase.DbConnectionFactory.TryGetConnection(DbConnection owningConnection, TaskCompletionSource`1 retry, DbConnectionOptions userOptions, DbConnectionInternal oldConnection, DbConnectionInternal& connection)
   at System.Data.ProviderBase.DbConnectionInternal.TryOpenConnectionInternal(DbConnection outerConnection, DbConnectionFactory connectionFactory, TaskCompletionSource`1 retry, DbConnectionOptions userOptions)
   at System.Data.SqlClient.SqlConnection.TryOpenInner(TaskCompletionSource`1 retry)
   at System.Data.SqlClient.SqlConnection.TryOpen(TaskCompletionSource`1 retry)
   at System.Data.SqlClient.SqlConnection.Open()
   at Dynamicweb.Data.DatabaseConnectionProvider.CreateConnection()
   at StandardWebshop.CustomCode.Solution.Factory.GlimpseDatabaseConnectionManager.CreateConnection() in D:\VSO Agents\00TFS01-norriq\_work\43\s\Src\StandardWebshop\CustomCode\Solution\Factory\GlimpseDatabaseConnectionManager.cs:line 19
   at Dynamicweb.Content.Management.Setup.CanConnectToDatabase(String server, String database, String username, String password, String connectionString, Boolean useIntegratedSecurity) in D:\sources\Dynamicweb\Dynamicweb9\06 - Dynamicweb Host\Dynamicweb\Dynamicweb-9.3\Dynamicweb\Content\Management\Setup.vb:line 106
ClientConnectionId:958fd7e2-43ba-4e1c-a4c9-3b889dd1b61b
Error Number:-2,State:0,Class:11