How does a pop mail client know which webmail messages to download?

thor

I have been undertaking a major refit of my pc and that involed having to reinstall all my apps including my pop email client thunderbird.
I use it to download emails off my virginmedia webmail account.
It, version 13.0.1 is a newer version to the one I had before and I am finding that it only downloads some of the emails from my webmail. I had about 70 messages which I normally would have retrieved but only 13 of them managed to get to Thunderbird. Further attempts just gives the 'There are no new messages etc'
There is no rhyme or reason to which emails made it across. Some from the same sender have downloaded while others have not and there is a mix of dates with older ones and newer ones being left out. So I am wondering with webmail what tells the pop client whether to download or not? I have marked all the ones which need downloading to 'unread' but that has made no difference so it can't be that.
Does anyone know?

russell_e

This sounds like a Virgin issue.

IIRC you need to prefix your username with recent: so it becomes recent:yourname@virginmedia.com

Have a look here
http://help.virginmedia.com/system/selfservice.controller?CONFIGURATION=1002&PARTITION_ID=1&TIMEZONE_OFFSET=&USERTYPE=1&VM_CUSTOMER_TYPE=Cable&CMD=VIEW_ARTICLE&ARTICLE_ID=37916

thor

I used the 'recent' prefix and got the 30 days worth of emails including the ones that didn't make it. Hopefully now it will start working properly after I drop prefix. I wonder if my thunder migration to a different have drive could have confused virginmedia's mail servers into thinking I was using a different mail client(which technically I was with the thunderbird upgrade) as the recent trick was designed for this purpose.
That advice is well appreciated Russell. Thanks:)