With the standard login settings, Gmail does not do a normal implementation of a POP account.

A normal pop account behaves like this:
- The client software (like outlook) logs in an requests a list of Email IDs that are currently residing on the server
- The client sees what emails it is missing and can choose to just download the headers of the  missing emails, or the entire emails

A Gmail pop account behaves like this:
- The client software (like outlook) logs in an requests a list of Email IDs that are currently residing on the server
- Gmail sends back a list that ONLY includes the email IDs of emails that have come in SINCE THE LAST TIME the account was accessed from a pop client (regardless of who/where that pop client is/was). From the perspective of the POP client, it thinks these are the only emails on the server.  This saves a lot of band width and assumes the same pop client is always accessing the server.

Unfortunately, if two computers (your home PC and your work PC for example) access a POP account, you'll only get email on whichever computer checks at the time (leading to lots of confusion and "missing" email).  Using a Palm Pilot or Black Berry causes the same problem.

Gmail does provide a work around (read carefully) that will make it behave like a normal POP mail server:

Instead of configuring your POP client to login with the username like:
ecampbell@cleanair.com

You can specify your email address with the word "recent:" on the front of it like this:
recent:ecampbell@cleanair.com

This forces the issue of returning an entire list of Email IDs (last 30 days only.)

Caution 1: depending on how much email you have on the server, this can cause a delay every time you check email.   If you, for example, have 30,000 email on
Caution 2: The first time you do this, you will receive in your in box the last 30 days worth of emails currently residing on the server, regardless is you have already downloaded them. Translation: lots of duplicates. Simply delete them (the duplicates) and it should behave normally after that first login.

Benefit: If you do this you WILL get emails that are sent to yourself.

 

 

This assumes the original copy of the email has been read & the new copies are all unread....

Sort these unread copies out & delete the unread copies.

To separate the unread copies, go to View: Arrange By: Current View: Unread Messages in this Folder

Delete, Delete, Delete, etc...   (shift click to select many emails at once & hit the delete key)

NOTE: it's probably a good idea to not delete the last day or so of duplicates (and instead go through these most recent ones manually as a precaution)

 

There are two kinds of receipts.  Google completely prevents the use of Delivery Receipts (spam prevention measure). 

 

Read Receipts are allowed BUT many clients don't respond by default.  Specifically, many IMAP clients (again, a growing trend) do not reply to receipt requests.

 

FYI: Blocking receipts is, to some extent, a growing trend as spammers use receipts to find their targets.

 

 

So far, it seems it's nothing to worry about as Outlook will just retry (and eventually succeed) when you first hook up via IMAP.   Generally, this only happens if you have several thousand emails on the server.

 

POP accounts download email to your hard drive...  so when you aren't on the network, all the email you downloaded is still on your hard drive (including Word/Excel attachments).

IMAP is much more like having a continuously connected window to the gmail server in California.  It has a lot of benifits (especially if you use multiple devices to access email) but also a significant downside: The default settings of Outlook leave attachments on Google's server and if you disconnect from the network, you can't access these attachments.   The picture below shows how to change Outlook's default behavior.   (

 

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