I currently run 5 threads for hotmail, we send out a fair amount of mail (~ 1 million / week). I don't see the queue building for hotmail being a problem. The problem is they are reporting 554, so at that point LSMTP bounces the message instead of retrying. I have had previous problems with them putting email into people's junk folders, so I instructed users to add the list address to their E-Mail Lists Area under preferences and this would solve the problem. I wonder if they are now filtering this at the SMTP protocol level? John Traweek Senior Account Director Publishing Concepts, LP 12840 Hillcrest Rd, Ste 230 Dallas, TX 75230 Phone - 972.774.3280 Fax - 972.774.3284