Asp.net (vb.net) fix

I need to send data to a remote URi from within a vb.net application. I have been given a PHP script and a basic spec and from those I have managed to develop the code but I just can't get the required results and the company which owns the data is not able to provide support for aspp.net

So in simple terms i need to send a request to uri which includes a querystring of data, authenticate the request and then read the response.

I've tried it manually so I know it works ok but when I use my code it doesn't work

string server = "http://server"

string poststring = "param1=ab&param2=cd"

Dim linkurl As String = server & "?" & poststring

Dim requestURI As Uri = Nothing

Uri.TryCreate( _
linkurl, _
UriKind.Absolute, _
requestURI)

Dim nc As New NetworkCredential(username, password)

Dim credentialCache As New CredentialCache

credentialCache.Add(requestURI, "Basic", nc)

Dim httpRequest As HttpWebRequest = HttpWebRequest.Create(requestURI)

httpRequest.Credentials = credentialCache

httpRequest.Method = WebRequestMethods.Http.Get

Dim uploadResponse As HttpWebResponse
uploadResponse = httpRequest.GetResponse

Dim responseReader As New StreamReader(uploadResponse.GetResponseStream())
postResponse = responseReader.ReadToEnd()
responseReader.Close()

If you think this is something you can fix let me know and I'll send you the uri, arguments and username, password

I need a solution that will work in Virtual Studio 2005