database - Connection to MySQL issue -


i make connection between program in vb.net , sql database. code this:

 public function connecter()     dim connexion string = "server=197.28.178.33;database=test;uid=userid;pwd=xxxxxxxxxpassxxxx;"     dim conn mysqlconnection = new mysqlconnection      conn.connectionstring = connexion     conn.open()     return conn end function private sub form1_load(sender object, e eventargs) handles mybase.load     dim lecteur mysqldatareader     dim requete string     connecter.close()     connecter()     requete = "select * article"     dim commande new mysqlcommand(requete, connecter)     lecteur = commande.executereader     while lecteur.read         combobox1.items.add(lecteur.getstring("description"))     loop     connecter.close() end sub

but error appears:

an unhandled exception of type 'mysql.data.mysqlclient.mysqlexception' occurred in mysql.data.dll additional information: unable connect of specified mysql hosts.

what cause of error?

i don't understand problem , how can verify if communicate server? , how i'm sure server running


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