Editing records directly is very slow compared to querys.
You need to somehow open the text file in a format that you can generate a query from and the easiest way to do that (that I can think of) is to link the text file as a table as I said above.
Because the file is linked you can replace it whenever you get a new file (as long as the new file has the same filename and format.)
So, say the users are using live.accdb.
Maybe you don't want to change/redistribute that db, so you could create the link in a new db, e.g. 'txtlnk.accdb'.
Then you execute SQL to transfer the data between the two. e.g.
<html><head><script language=vbscript>
ACC2007 = "provider=microsoft.ace.oledb.12.0;data source=%path%;"
txtlnkPath = "X:\db\txtlnk.accdb"
LiveDBPath = "X:\db\live.accdb"
Function GetDBStr(db,path)
GetDBStr = Replace(db, "%path%", path)
End Function
sub main()
Dim con 'As New ADODB.Connection
set con = createobject("ADODB.Connection")
con.open GetDBStr(ACC2007,txtlnkPath)
con.execute "select * into [" & LiveDBPath & "].NewTable from [csvlink]"
run.innerhtml="done"
end sub
</script></head><body>
<div id='run'><button onclick='main'>run</button></div>
</body><html>