Vba to send sms to mobile number

Ummm,

Thanks for your response, However

I am getting an error
"Compile error
Duplication declaration in current scope"

Getting error at

Dim myMsg As String

Here is my full code:

Sub Sample()
    Const sUser As String = "9999999999"
    Const sPw As String = "Password"
    Const sId As String = "SMSBUZ"
    Const baseUrl As String = "http://smsidea.co.in/sendsms.aspx"
    Dim sReq As String, myMsg As String, dest As String
    Dim resp As String
    Dim myMsg As String
With Sheets("Sheet1")
    myMsg = "Hi you made a sales to " & .Range("C3").Text & " with " & .Range("Q42").Text & "."
End With
    myMsg = encodeURL(myMsg)
    dest = "999999999"
    sReq = "?mobile=" & sUser & "&pass=" & sPw & "&senderid=" & sId & "&to=" & dest & "&msg=" & myMsg
    With CreateObject("MSXML2.xmlHttp") 'May need to change this to MSXML2.ServerXMLHTTP
        .Open "POST", baseUrl & sReq, False
        .setRequestHeader "Content-type", "application/x-www-form-urlencoded" 'You will need to find from vendor what headers are needed
        .Send
        resp = .responseText
    End With
End Sub