* Removed the "here's why some specific messages might be flagged as spam" in favor of a general explanation
* Bullet points, as a sort of checklist for people to go through (most likely to least likely)
* added, "whitelist email@example.com specifically", in case people can't whitelist a domain.
* took out the "make sure you enabled commenting!!" bit, that seems extraneous. you won't get comment notifications for comments that DON'T EXIST. :P
* took out the "check parental controls", as I don't think I've seen a recent case where that was actually the case.
* took out the "it's not our fault, except when it is" paragraph.
If you are not receiving any emails from LiveJournal, please verify that the email address on your account is correct by visiting your Edit Profile page.
If you are not receiving comment notification emails, check to ensure that you have commenting enabled and that you have enabled the "Email notifications" option on the Comment Settings page. If you have enabled HTML emails, try turning this option off. Also, ensure that your email address is validated.
Check the space available in your email account. Many email service providers place limitations on the amount of email you can store in your mailbox. If you have space available in your mailbox, then it is likely that some or all of your LiveJournal email is being filtered or blocked as spam or junk mail. Check the spam or junk mail filters on your email account. If it is possible for you to adjust or edit them, add livejournal.com to the "allowed senders" list, sometimes called a "whitelist". It may also help if you add livejournal.com and/or 220.127.116.11 (LiveJournal's IP address) to your address book. If it is not possible for you to adjust or edit your filters, you may need to disable them entirely. Also, certain Internet services provide parental controls which can interfere with proper email delivery.
If you have adjusted or disabled the spam or junk mail filters on your e-mail account, or do not know how to do so, and are still not receiving LiveJournal e-mail, you will need to contact your e-mail service provider for further assistance, and tell them that you are not receiving legitimate e-mails from livejournal.com. Many e-mail providers are not aware of the mail filters they have in place.
Also, it is possible that your email provider is using filters that your account cannot control. Many email providers do not notify their customers that such filters are used. In these cases, it is possible that mail from LiveJournal is being blocked for a variety of reasons. Validation emails may be blocked because they contain instructions to click on a link, which is a common method that spammers use in their emails. Comment notifications may be blocked because of the subject line "Reply to your post", since that is also a common falsified subject line used by spammers. Another possible reason is that LiveJournal sends a high volume of automatic emails. Still other email providers may simply block LiveJournal entirely, for reasons of their own which they might not disclose. You must contact your email service provider directly to inquire about the filters they use and whether they may be affecting email delivery to your account.
If, after following all of the above suggestions, including contacting your email service provider, you are unable to receive emails from LiveJournal reliably, you may want to choose a different email address for receiving LiveJournal email. Please note that your new email account may suffer from the same types of restrictions, and you may have to try several different email providers until you find one which works with LiveJournal reliably.
LiveJournal has no control over any email message once it has been sent. If LiveJournal's email server is functioning properly and sending email messages in a timely manner, there is nothing further LiveJournal or its volunteers or staff can do to ensure that you receive the messages that are sent.