How do I configure my mail client to not fill my email?
Whenever you set up a new email account in a mail program, the program prompts you to choose among POP and IMAP. If you wish to download your emails on your computer and then delete them from the server, you should choose to set up your account as a POP account. By default, the POP3 mail protocol do just that - downloads your emails to your local mail program and then deletes them from the server, so you do not fill your email.
If the same account has been set in more than one email programs, you can download your emails on all your devices before you delete them from the server, your mail programs provide the opportunity to let a copy of messages on the server, for the period you choose.
For example, in Microsoft Outlook 2010, to enable this feature, the Account Settings you will go to the Advanced. In this tab, under Delivery, you will check the box next to Leave a copy of messages on the server. Then check the box next to Remove from server after and choose after how much time will remove the messages from the server. After making your changes, click OK to save your settings.
If you do not see this option, it is likely you have already set up your account as an IMAP. In this case, if you want to change your account to POP, you'll need to set up your account from the beginning.