It is all about anti-spam. Many have the wrong impression or little understanding of anti-spam. Even a lot of IT admins have a faint idea on anti-spam.
Emailing is more like a daily routine for many. Ask yourselves on how much do you understand on anti-spam. Most will tell you spam emails are those unwanted emails. But how?
Hopefully, I can make this understanding better. When someone told you I’m receiving a lot of spam emails each day, there are a few things to ask and examine. How do you determine those are spam emails? Where did these emails go to? If the subject has ‘SPAM’ classification? What kind of anti-spam solution do you have?
Anti-Spam has become very complicated. Especially those have installed anti-virus application on their computer has an anti-spam function too. The double filtering creates a lot of guessing games. We have cases whereby the email was quarantined by the local computer without users noticing it. However, the users plastered the server admin on such an event.
Honestly, there are a few ways to determine a spam email. These rules are predefined and read by machines. The most common method is to use realtime blackhole list known as DNSBL The lists are maintained by various spam agencies. Control panels and mail servers etc use these list provided free to reject or define spam emails.
Yes, it is common but less effective against spam emails. The more effective methods are combining a few like detecting spammy words, the type of charset, trusted senders and training the anti-spam system on the types of emails you wanted to receive. A good anti-spam system allows you to quarantine, reject or inject the spam classification into the subject that these emails have classified as a spam email.
You may have the best anti-spam system but I realized there are organizations have many false-positives a lot of tuning from time to time. The sender can be a newcomer, his or her email was rejected because it has violated the anti-spam rules even it was genuine. I have found the courier and logistics companies cannot have very stringent anti-spam rules and you need to check the process often to avoid unnecessary delays.
I want to say you need a good mail server admin to minimise the hiccups even you have a good anti-spam system. When this has happened, he or she is able to check from the header and do the necessary adjustments in quicker turnaround.