C#

Cannot cast the underlying exported value of type 
'Microsoft.Practices.Prism.MefExtensions.Regions.Behaviors.MefDelayedRegionCreationBehavior (ContractName="Microsoft.Practices.Prism.Regions.Behaviors.DelayedRegionCreationBehavior")' 
to type 
'Microsoft.Practices.Prism.Regions.Behaviors.DelayedRegionCreationBehavior'.

// Add any attachments from the product web page
if (message.FilePath != null )
{
    using (var fileStream = File.OpenRead(message.FilePath))
    {
        var attach = new Attachment(fileStream, message.FilePath);
        mailMessage.Attachments.Add(attach);
        await fileStream.FlushAsync();
    }
}

// Load the SMTP Credentials                
using (var smtpClient = SendEngineAsync.Create_SMTPClient(smtpC))
{
    // Fire the send engine async
    var result = await SendEngineAsync.SendEmailAsync(smtpClient, mailMessage, 5);
    SendEngineAsync.ProcessSendResult(resend, result);
}

public partial class CreateQuotationForm : UserControl
{
    private readonly string _quotationId = ObjectId.GenerateNewId().ToString();
    private ImageList _imageListSmall;
    private ImageList _imageListLarge;
    private List<QUOTATION_ITEMS> _quotationItems;

    public delegate void SaveClickEventHandler(object sender, EventArgs e);
    private SaveClickEventHandler saveClick;
    public event SaveClickEventHandler SaveClick
    {
        add { saveClick += value; }
        remove { saveClick -= value; }
    }

private void OK_Button_Click(object sender, EventArgs e)
{            
   //Pass the click
}