Open File On FTP Server

I try to run a macro on my workbook everytime I open it by getting the data from the ftp file. This will be the service number for my customer. Both the excel and the data file are located in the ftp, so that I can retrieve the file wherever I go. Basically I got some code from the internet which work fine on the local network, but once it come to ftp server I am stuck there.

Public Function NextSeqNumber(Optional sFileName As String, Optional nSeqNumber As Long = -1) As Long
Const sDEFAULT_PATH As String = "Ftp://mycompany.com"
Const sDEFAULT_FNAME As String = "Service.txt"
Dim nFileNumber As Long
nFileNumber = FreeFile
If sFileName = "" Then sFileName = sDEFAULT_FNAME
If InStr(sFileName, Application.PathSeparator) = 0 Then _
sFileName = sDEFAULT_PATH & Application.PathSeparator & sFileName
If nSeqNumber = -1& Then
If Dir(sFileName) <> "" Then
Open sFileName For Input As nFileNumber
Input #nFileNumber, nSeqNumber..................