Hello, I have a drop down list with some items. I need to disable some items (not selectable) from this list. How can i implement this. Please reply..

I have deployed a project in ftp location. It is a .net with mysql application. But i am trying to open the site getting the execption like the following "Unable to connect to any of the specified MySQL hosts.***********System.Net.Sockets.SocketException: No connection could be made because the target machine actively refused it 174.143.28.30:3306 at System.Net.Sockets.Socket.EndConnect(IAsyncResult asyncResult) at MySql.Data.Common.StreamCreator.CreateSocketStream(IPAddress ip, Boolean unix) at MySql.Data.Common.StreamCreator.GetStream(UInt32 timeout) at MySql.Data.MySqlClient.NativeDriver.Open() " But i could connect the remote mysql server from my local application.Its working fine at time.. If anybody knows why this occur,please replay .Thanks in advance

Please give me a link or explain how will i write the code for checking duplicate user name is existing while trying to insert new one by using core ajax coding