You are working exactly the way I used to before the migration.
The problem is that POP3 is now GMail's bolted-on interpretation of the way POP3 should work, on what was designed as a webmail solution, rather than true POP3 standards. Specifically it seems to ignore client-side instructions when a POP3 connection is made and the settings on the server side (accessible from Webmail) may be set to mark an email as read at the first POP3 connection, or to be deleted, hence not delivered to your second client when you connect from that.
Email deleted on the server doesn't actually get deleted until it's 30 days old. Therefore there is a workaround if you want to continue to use POP3, or an alternative if you want to consider switching protocols.
You have two choices.
- if you want to continue using POP3 as your chosen method of connection then use "recent:name@ntlworld.com" as your account name in the POP3 settings on all your clients. Using the "recent:" should ensure you receive mail in all clients as it ignores the fact it's previously been read (or deleted I believe if within the 30 days).
- alternatively, switch to using IMAP as your method of connection which basically ensures your mailbox is synced across the server and all clients (to the extent that if you create a folder in Outlook it will appear in your webmail as a GMail-style label).
I've done the latter and got used to the different way things work. If you do switch to IMAP, make sure you read up on what happens when you carry out particular actions in the email client. For example, deleting an item from your inbox doesn't delete it, it merely removes the "inbox" label from it. A copy remains in "all mail". To delete you have to drag it to the GMail bin, from where it will disappear in 30 days unless you manually choose to purge it sooner.
Hope this helps.
P.S. If you switch to IMAP you will need to make sure IMAP is turned on in the Forwarding and IMAP/POP3 options within Webmail.
You will also need to create new IMAP connections in your phone and in Outlook as they work differently i.e. it's not simply a case of changing the POP3 connection to point at the IMAP server). As well as the default PST/personal folder containing your calendar and To Do list etc. you will see a new mailbox called name@ntlworldcom but it's not a PST since effectively it's just displaying an IMAP connection to what's on the server. The inbox within your default personal folder will become redundant but you can't delete it as it holds the calendar, To Do list etc.