Public Function IsValidEmail(strEmail As String) As Boolean
Dim names, name, i, c
IsValidEmail = True
names = Split(strEmail, "@")
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(strEmail, "..") > 0 Then
IsValidEmail = False
Exit Function
End If
End Function