Object reference not set to an instance of an object

[Zack Catton]

I have a C#4 WPF VS2010 application that connects to our MySQL 5 database using .net connector 6.3.6.0.

It works fine but if a user stays inactive for a while it starts giving me this error.

Object reference not set to an instance of an object.

at MySql.Data.MySqlClient.NativeDriver.ExecutePacket(MySqlPacket packetToExecute)
at MySql.Data.MySqlClient.NativeDriver.SendQuery(MySqlPacket queryPacket)
at MySql.Data.MySqlClient.Driver.SendQuery(MySqlPacket p)
at MySql.Data.MySqlClient.Statement.ExecuteNext()
at MySql.Data.MySqlClient.PreparableStatement.ExecuteNext()
at MySql.Data.MySqlClient.PreparableStatement.Execute()
at MySql.Data.MySqlClient.MySqlCommand.ExecuteReader(CommandBehavior behavior)
at MySql.Data.MySqlClient.MySqlCommand.ExecuteNonQuery()

I use an object that is created when the class is constructed:

this.conn = new MySqlConnection("server=***.***.***.***;user=*****database=*****;port=*****;password=*******;default command timeout=30;");

Every time I run a query I do the following method first.

public bool connOpen()
{
if (this.conn.State != ConnectionState.Open) conn.Open();
if (this.conn.State == ConnectionState.Open) return true;
return false;
}