cdo SMTP errors in Vista -- (worked) in XP

After switching from XP to Vista, I'm having problems with some code that makes use of cdo (I'm using my ISP email account to send mail via smtp).Initially I got back an error: The 'SendUsing' configuration value is invalid.But after configuring Windows mail and Outlook with the email account (a step that used to resolve cdo problems on XP), the same code produced an entirely different error:Error reported: 2147220975. The message could not be sent to the SMTP Server. The transport error code was 0x80040217. The server response was not available.Sending via Windows mail or Outlook works fine, but I need to send via cdo code.Note that this code worked fine in XP. The code is as follows (I've already tried setting cdoSMTPUseSSL to false, but it didn't help.): Const ksFrom As String = "SenderName@comcast.net" Dim oCfg As cdo.Configuration Dim oMsg As cdo.Message Set oCfg = New cdo.Configuration With oCfg.Fields !cdoSendUsingMethod = cdoSendUsingPort !cdoSMTPServer = "smtp.comcast.net" !cdoSMTPServerPort = 25 !cdoSMTPConnectionTimeout = 120 !cdoSMTPAuthenticate = cdoBasic !cdoSMTPUseSSL = True !cdoSendUserName = "SenderName" !cdoSendPassword = "password" .Update End With Set oMsg = New cdo.Message With oMsg Set .Configuration = oCfg .To = sTo .From = ksFrom .Sender = ksFrom .Subject = sSubject .ReplyTo = "SenderName2@gmail.com" If Len(sCC) Then .CC = sCC If Len(sBCC) Then .BCC = sBCC If Len(sFileName) Then .AddAttachment sFileName If Len(sMsg) Then .TextBody = sMsg .Send End With Set oMsg = Nothing Set oCfg = Nothing EmailDocs = True Exit Function