Toad World® Forums

MySQL 5.5 Pam Authentication

I have the pam_authentication plugin installed on a MySQL 5.5.19 server. I log in without issue from the command line and also from MySQL Workbench. When trying to log in with Toad for MySQL I get the following error.

MySQL Database Error: Client does not support authentication protocol requested by server; consider upgrading MySQL client

I also tried connecting with an SSH connection and using the MySQL libraries. In that case I get the following error.

Unable to load libmysql.dll.
Stack Trace:
at Devart.Data.MySql.l.d()
at Devart.Data.MySql.bp…ctor()
at Devart.Data.MySql.l…ctor()
at Devart.Data.MySql.MySqlInternalConnection.Connect(MySqlConnection owner, String userId, String password, String host, String database, Int32 port, Int32 connectionTimeout, MySqlProtocol protocol, Boolean compress, Boolean clientInteractive)
at Devart.Data.MySql.MySqlInternalConnection…ctor(o connectionOptions, MySqlConnection owner)
at A_0, Object A_1, DbConnectionBase A_2)
at Devart.Common.DbConnectionFactory.a(DbConnectionBase A_0, u A_1)
at Devart.Common.DbConnectionFactory.a(DbConnectionBase A_0)
at Devart.Common.DbConnectionClosed.Open(DbConnectionBase outerConnection)
at Devart.Common.DbConnectionBase.Open()
at Devart.Data.MySql.MySqlConnection.Open()
at Quest.Toad.Db.Connection.OpenConnection(IDbConnection connection)
at Quest.Toad.MySQL.MySQLConnection.OpenConnection(IDbConnection connection)
at Quest.Toad.Db.Connection.AllocConnection()
at Quest.Toad.Db.Connection.Connect(Boolean notify)
at Quest.Toad.Db.Provider.BackgroundConnector.CreateBackgroundConnection()

An attempt was made to load a program with an incorrect format. (Exception from HRESULT: 0x8007000B)
Stack Trace:

Is there a workaround to get this working?

Thank you,


Message was edited by: regan.jeremy

I solved this problem by downloading the 32bit version of MySQL 5.5.19 for Windows and copying the libMySQL.dll to the Toad installation directory. I then added this path to my user PATH environment variable. In my case it was located at C:\Program Files (x86)\Quest Software\Toad for MySQL Freeware 6.0.

As with the previous post I still needed to use an SSH connection and check Use MySQL libraries.