Hi
I hope I've placed my thread in the right place.
Can someone tell me why is it that people(outside the network) are sending users (sometimes it happens to me ass well) in my network mail but it they only get it 5 hours or so later(time varies)

Any suggestions is gladly appreciated
Thanx in advance

details

I have a network of 65 workstations about 30 of them is connected to the email server.all was going well up until a week ago.I haven't made any changes(that I know of)-our second network admin also claims not to have changed anything.I did check for changes though and in the brief pressured moment found nothing.
Like I said users are complaining they are receiving emails that was send by to them five hours ago already.There is no sign that my server is causing the delay(it might be but where do I look if its keeping it hanging for the amount of time).
remember it happens on different machines.
If someone can provide me with some things I can look at Ill appreciate it

what MTA do you use, what is the SMTP atchitecture, network topology, DNS settings, logs, RBL listings
I can't guess what email server you are using, since there is no default server, and I can't see you logs man

k, my bad ill inform after gathering the info @work