Setup is Windows XP Pro.For 5+ Years I have been using System.Web.Mail/SMTP.Send(Message) in various programs written with Visual Studio 2003 / VB.Net and ASP.Net to send me an E-Mail advising certain actions or errors/bugs caught by Try/Catch.On or just after 29th September this facility just stopped working with all Indirect E-Mails being dumped into c:\inetpub\mailroot\queue. Normal (Direct SMTP) via Outlook is working fine.This has affected two other machines running Windows XP and one machine running Server 2003. In addition, the ISPs for these machines are all different.Initially I assumed (wrongly) that a Windows Update was responsible but just by luck I happened to have an HDD amongst my odds-and-ends that I replaced last January during a Re-Build. I re-installed this, turned auto Updates off and tested - Result exacty the same, no Indirect SMTP.None of my programs have been changed and I'm now totally at a loss to find anything else to try.Comments and/or suggestions would be most welcome!David Smith1 person got this answerI do too