Attaching a document(from sharepoint library) to an email event

Hi guys, I am trying to attach a document from a sharepoint document library to an email event message, but all my workflow instances go to an error state :

Could not load file or assembly 'Microsoft.SharePoint.Library, Version=14.0.0.0, Culture=neutral, PublicKeyToken=71e9bce111e9429c' or one of its dependencies. The system cannot find the file specified.

I have referenced the dll but I am still getting the error, please advice

Thanks in advance.

Please find the server object model code below:

can i use the client object model instead of the server object model ???

try

{

].Value.ToString();

(siteUrl))

{

web = site.OpenWeb())

{

web.AllowUnsafeUpdates =

;

//ApplicantDocuments

;

+ fileName;

file = web.GetFile(url);

//

[])file.OpenBinary();

System.IO.

(buffer);

));

web.AllowUnsafeUpdates =

;

}

}

}

ex)