ci riprovo.... 
codice:
//SALVO ALLEGATI
if (item.Attachments.Count > 0)
{
for (int x = 1; x <= item.Attachments.Count; x++)
{
string retrive_type = item.Attachments[x].FileName.ToString();
string type = retrive_type.Substring(retrive_type.Length - 3);
string CONTENT_TYPE = "";
switch (type)
{
case "doc":
CONTENT_TYPE = "application/msword; name=" + item.Attachments[x].FileName.ToString();
break;
case "xls":
CONTENT_TYPE = "application/vnd.ms-excel; name=" + item.Attachments[x].FileName.ToString();
break;
case "lsx":
CONTENT_TYPE = "application/vnd.ms-excel; name=" + item.Attachments[x].FileName.ToString();
break;
case "pdf":
CONTENT_TYPE = "application/octet-stream; name=" + item.Attachments[x].FileName.ToString();
break;
case "gif":
CONTENT_TYPE = "application/gif; name=" + item.Attachments[x].FileName.ToString();
break;
case "png":
CONTENT_TYPE = "application/octet-stream; name=" + item.Attachments[x].FileName.ToString();
break;
case "rar":
CONTENT_TYPE = "application/octet-stream; name=" + item.Attachments[i].FileName.ToString();
break;
case "zip":
CONTENT_TYPE = "application/octet-stream; name=" + item.Attachments[x].FileName.ToString();
break;
default:
CONTENT_TYPE = "application/octet-stream; name=" + item.Attachments[x].FileName.ToString();
break;
}
FILENAME = item.Attachments[x].FileName.ToString();
CONTENT_SIZE = item.Attachments[x].Size.ToString();
//Salvo il file su FS
item.Attachments[x].SaveAsFile("C:\\ecc ecc\\Visual Studio 2010\\Projects\\MailReader\\" + FILENAME);
//
FileStream fs = new FileStream("C:\\ecc ecc\\Visual Studio 2010\\Projects\\MailReader\\" + FILENAME, FileMode.Open, FileAccess.Read);
BinaryReader br = new BinaryReader(fs);
Byte[] bytes = br.ReadBytes((Int32)fs.Length);
br.Close();
fs.Close();
//INSERIMENTO ARTICLE_ATTACHMENT
MySqlDataReader reader_att_id;
int article_id = 0;
SQLQuery_att_id = "SELECT MAX(ID) AS ID FROM `otrs`.`article`";
db.Execute_Query(SQLQuery_att_id);
reader_att_id = db.Execute_Reader(SQLQuery_att_id);
while (reader_att_id.Read())
{
article_id = int.Parse(string.Format("{0}", reader_att_id["ID"]));
}
SQLQuery = " INSERT INTO `otrs`.`article_attachment` (ARTICLE_ID, FILENAME, CONTENT_SIZE, CONTENT_TYPE, CONTENT_ID, CONTENT_ALTERNATIVE, CONTENT, CREATE_TIME, " +
"CREATE_BY, CHANGE_TIME, CHANGE_BY) VALUES (" + article_id + ", '" + FILENAME + "', '" + CONTENT_SIZE + "', '" + CONTENT_TYPE + "',NULL , NULL ,'" + bytes + "', now(), 0, now(), 0);";
if (!db.Execute_Query(SQLQuery))
throw new System.Exception("Si è verificato un errore durante il salvataggio del ticket.");
}
}