Encoding Problem :(

[CatchItBaby]

Dim buffer As Byte()

System.Web.HttpUtility.UrlEncode(System.Web.HttpUtility.UrlEncode(username)) 'username = "CatchItbaby - 1988"
buffer = Encoding.UTF8.GetBytes(data)


postStream = re.GetRequestStream()
postStream.Write(buffer, 0, buffer.Length)
 postStream.Close()

whenever username contain minus sign it converted into � how to correct this problem

Thanks