Is your account IMAP? Does your provider auto delete mail older than 2 weeks? Or does your phone?

I don't know what IMAP is. My phone keeps the messages for longer than 2 weeks, but often when I receive emails on my phone, they don't show up on the desktop

Thanks. I am using Cox webmail. Going directly to the Cox site shows the same small number of emails, My other computers keep them all. I will try Cox to see if there is some kind of syncing going on.

Ok so you need to know. 1. Is your account IMAP or POP. This applies both to your phone and to Thunderbird. In Thunderbird right click the account in the folder pane, select settings. Select server settings for the account In the setting that display the first thing on the right is either IMAP or POP.

Further down on POPO accounts there is an option to leave messages on server for at most. But the default value for that is not 14 days. So check it, but I do not think it is the issue.

My "guess" is your phone is pop and your desktop/Thunderbird is IMAP.

2. Is your phone set to remove mail from the server when it downloads it.

 This is a very common setting for some phone apps.

3. Does your provider have a retention setting on emails in the inbox or in the account. Who is your mail provider?

What goes on here.... Are the messages out of order, or am I.

In Thunderbird right click the account in the folder pane, select settings. Select server settings for the account In the setting that display the first thing on the right is either IMAP or POP.

If it is IMAP then there is synchronization going on. If it is PoP there is not. That is one of the two principal differences between IMAP and POP. The other is POP only downloads the inbox, IMAP gets all folders. So your sent from Thunderbird shows in Sent on Cox etc.

Cox retention policy is detailed here http://www.cox.com/residential/support/internet/article.cox?articleId=4e311ca0-d674-11e5-f852-000000000000

Regarding the 3:03 post: Thank you for helping Matt! Desktop email is IMAP. Setting says it will leave messages until I delete them, so confused! Can't figure out what my phone is. Cant find anything noteworthy in settings. My mail provider is TWC (Roadrunner) What is most puzzling - did not have these issues up until Sept. Interesting fact: when my husband deletes messages on his email ( same setup & email as mine) my messages delete

His is also IMAP. IMAP synchronizes all devices that access the email account with the server copy. Very handy for those that want their mail to have the same messages wherever they use email. Not very helpful for those like yourself and your husband who it am guessing are sharing an email address. I would suggest that both you and your husband set your accounts up again using the pop mail protocol. TWC offers both options.

but before you make decisions read over this short article on IMAP and POP. so you are not flying blind into the future. https://support.mozilla.org/en-US/kb/glossary-terms-including-types-accounts#w_mail-accounts

TY you for taking time to address this Matt. This particular email important due to a business, & helpful that we could access it in many ways. Husband also has another acct w/Outlook for a different business - I don't like that one. Will follow your advice asap & post the outcome, unless more questions arise!

TWC is somewhat helpful - at least one can usually talk to a live person!

Thanks. I am changing from IMAP tp POP