Sub TestPOSTBTCe()

Dim APIkey As String
Dim SecretKey As String
Dim NonceUnique As Long
Dim postData As String

Dim SecretKeyByte() As Byte
Dim messagebyte() As Byte
Dim Sign As String

NonceUnique = DateDiff("s", "1/1/1970", Now)

'BTC-e
TradeApiSite = "https://btc-e.com/tapi/"
APIkey = "THIS IS WHERE YOUR API-key goes"
SecretKey = "And here goes your private key"
postData = "method=getInfo&nonce=" & NonceUnique
Sign = HexHash(postData, SecretKey, "SHA512")

' Instantiate a WinHttpRequest object and open it
Set objHTTP = CreateObject("WinHttp.WinHttpRequest.5.1")
objHTTP.Open "POST", TradeApiSite, False
objHTTP.SetRequestHeader "Content-Type", "application/x-www-form-urlencoded"
objHTTP.SetRequestHeader "Key", APIkey
objHTTP.SetRequestHeader "Sign", Sign
objHTTP.Send (postData)
objHTTP.WaitForResponse

Debug.Print postData, "-", objHTTP.ResponseText

Set objHTTP = Nothing

'{"success":0,"error":"invalid sign"}
'{"success":1,"return":{"funds":{"usd":0,etc.

End Sub

Function HexHash(ByVal clearText As String, ByVal key As String, Meth As String) As String
    
    Dim hashedBytes() As Byte
    Dim i As Integer
    
    hashedBytes = computeHash(clearText, key, Meth)
    HexHash = ""
    For i = 0 To UBound(hashedBytes)
        HexHash = HexHash & LCase(HEX(hashedBytes(i)))
    Next
    
End Function
Function computeHash(ByVal clearText As String, ByVal key As String, Meth As String) As Byte()

    Dim BKey() As Byte
    Dim BTxt() As Byte
    
    BTxt = StrConv(clearText, vbFromUnicode)
    BKey = StrConv(key, vbFromUnicode)
    
    If Meth = "SHA512" Then
        Set SHAhasher = CreateObject("System.Security.Cryptography.HMACSHA512")
        SHAhasher.key = BKey
        computeHash = SHAhasher.computeHash_2(BTxt)
    ElseIf Meth = "SHA256" Then
        Set SHAhasher = CreateObject("System.Security.Cryptography.HMACSHA256")
        SHAhasher.key = BKey
        computeHash = SHAhasher.computeHash_2(BTxt)
    Else
        Set SHAhasher = CreateObject("System.Security.Cryptography.HMACSHA1")
        SHAhasher.key = BKey
        computeHash = SHAhasher.computeHash_2(BTxt)
    End If
End Function

Set objHTTP = CreateObject("WinHttp.WinHttpRequest.5.1")
objHTTP.Open "POST", TradeApiSite, False
objHTTP.SetRequestHeader "Content-Type", "application/x-www-form-urlencoded"
objHTTP.SetRequestHeader "Key", APIkey
objHTTP.SetRequestHeader "Sign", Sign
objHTTP.Send (postData)