Hi Guys, Thanks for all of the helpful emails so far, all very helpful but unfortunately this problem still persists. Perhaps I should make it clear what I do know is occurring and perhaps this will make it easier to reach the root of the problem: * We have a single list with no subscribers which has every other list on our Listserv server as a sublist, for simplicity I'll refer to this as the 'master list'. This master list is just used as a means of broadcasting, for contacting all Listserv users on our server whenever this is necessary, it is not used for anything else. Once again it has no subscribers. * The two users who are currently having problems receiving mails are both from separate companies and have separate domains. They are not related to each other in anyway. * Neither of these users are subscribed to any lists, I have searched and there is no reference to their email addresses or even domains in any lists we host. * I have tried every conceivable method of searching for references to them within the lists but cannot find any reference to them whatsoever, to all intents and purposes they do not exist as far as listserv is concerned. However when an email is sent to the 'master list' they still receive emails. Upon checking the Listserv web logs I can clearly see that the list has sent to their addresses, this means that they are not receiving the mails as the result of another list, the 'master list' is definitely sending to them directly. Although it shouldn't because they are not subscribed to any lists. You see the problem? It seems these users are somehow trapped within Listserv somewhere and I'm really not sure how to remove them now, this is hopefully where one of you kind, kind people will be able to help out! ;) I have checked the email headers of the users who have received the messages and you can clearly see that they have received these emails direct from our Listserv server, but we can see this already by looking at the master list log as mentioned above. Any thoughts on this problem would be much appreciated! Best Wishes and thanks in advance Shaun BTW, One more quick one, I have also had this problem recently (must be the weather in the UK!) if a user gets put into Listserv's Quarantine (i.e. sends too many similar mails in a short period and they are considered SPAM by Listserv) is it possible to somehow 'release' them from the automatic 48 hour ban from posting? I have read the literature but cant find any method of releasing a user who has been accidentally and incorrectly identified as a spammer! Once again suggestions are much appreciated!