System.ArgumentNullException: Value cannot be null. Parameter name: InString at System.Convert.FromBase64String(String s) at Encryption.DecryptSymmetric(String sToDecrypt) in C:\inetpub\AgenceMontreal\NetEvtMontreal\App_Code\Encryption.vb:line 31 at controls_formulaire.Page_Load(Object sender, EventArgs e) in C:\inetpub\AgenceMontreal\NetEvtMontreal\controls\formulaire.ascx.vb:line 55