Remote desktop connection using process.startinfo - vb.net-2010

Question

I have created an asp.net webpage and from the webpage I am using the code below to establish a remote desktop connection.
rdp.exe is a external file
Here is my code
Protected Sub BtnRemote_Click(ByVal sender As Object, ByVal e As EventArgs) Handles BtnRemote.Click
Dim Process As New System.Diagnostics.Process
Dim startinfo As New System.Diagnostics.ProcessStartInfo
startinfo.WindowStyle = System.Diagnostics.ProcessWindowStyle.Normal
startinfo.FileName = "C:\WINDOWS\system32\cmd.exe"
Dim path = "D:\rdp.exe"
startinfo.Arguments = path + "/v:" + txtTerminal.Text + " " + "/u:" + txtTerUser.Text + " " + "/p:" + txtTerPassword.Text
startinfo.UseShellExecute = False
Process.Start(startinfo)
End Sub
Everything is fine when I debug, but the system will not establish a remote connection.
But if I use the following command from command prompt, I am able to establish a remote connection.
E:\rdp /v:"IPAddress" /domain:"domain" /u:"username" /p:"password"

Answer 1

A problem i can see with this is within this line (Also Notice its got the Path, User, Password, and IP, BUT is missing the Domain Argument):
startinfo.Arguments = path + "/v:" + txtTerminal.Text + " " + "/u:" + txtTerUser.Text + " " + "/p:" + txtTerPassword.Text
as stated in your CMD arguments it needs to fit this format:
E:\rdp /v:"IPAddress" /domain:"domain" /u:"username" /p:"password"
However if you notice your startinfo.arguments doesn't contain a space in between the Directory and the IP Address Line so instead of reading it like this:
E:\rdp /v:"IPAddress" /u:"username" /p:"password"
it's reading it like this:
E:\rdp/v:"IPAddress" /u:"username" /p:"password"
just simply fix the line like this:
startinfo.Arguments = path + " /v:" + txtTerminal.Text + " /u:""" + txtTerUser.Text + """ /p:" + txtTerPassword.Text
I Also removed the Concatenations of + " " + because all you really need is a
space before the /'s and it will still work properly. Also notice that i have added extra quotes, because if the username supports spaces then when it goes to set the argument if the username contains a space then it will count them as two separate arguments quotes around it prevents it from being split into two different arguments
also instead of using CMD why not start the exe directly by
Dim p As Process
p.startinfo.FileName = "D:\rdp.exe"
p.StartInfo.WorkingDirectory = "D:\"
startinfo.Arguments = path + " /v:" + txtTerminal.Text + " /u:""" + txtTerUser.Text + """ /p:" + txtTerPassword.Text
p.Start()