ASP Mailbox Address verifier

'********************************************
' Function name: IsValidEmail
' Function: Check email address legality
' Parameters: Email----email address to check
' Return value: True----Email address is valid
' False----Email address is illegal
'********************************************
function IsValidEmail (email)
Dim names, Name, I, C
IsValidEmail = True
names = Split (email, "@")
If UBound (names) <> 1 Then
IsValidEmail = False
Exit function
End If
For each name in names
If Len (name) <= 0 Then
IsValidEmail = False
Exit function
End If
For i = 1 to Len (name)
c = Lcase (Mid (name, I, 1))
If InStr ("abcdefghijklmnopqrstuvwxyz_-.", c) <= 0 and not IsNumeric (c) Then
IsValidEmail = False
Exit function
End If
Next
If left (name, 1) = "." or Right (name, 1) = "." Then
IsValidEmail = False
Exit function
End If
Next
If INSTR (names (1), ".") <= 0 Then
IsValidEmail = False
Exit function
End If
i = Len (names (1))-InStrRev (names (1), ".")
If I <> 2 and I <> 3 then
IsValidEmail = False
Exit function
End If
If INSTR (email, "...") > 0 Then
IsValidEmail = False
End If
End Function