I'm assuming IMAP mail account.

Check settings:

• Right click on imap mail account name in Folder Pane and select 'Settings'
• Select 'Synchronisation & storage'
• Under 'Disc Space' section
• select 'Synchronise all messages locally regardless of age'
• select 'Don't delete any messages'
• click on 'OK'

Check Inbox:

• Right click on Inbox folder and select 'Properties'
• select 'Retention Policy'
• select 'Use my account settings'

OR

• uncheck 'Use my account settings'
• select 'Don't delete any messages'
• click on 'OK'

Thanks Toad-HAll for your reply but unfortunately non of the options you suggested worked. In case it has any bearing on things I have 2 computers at home, the 1st a desktop running Windows7 which shows all e-mails I've received from day one going back to 2013 in the inbox, and the 2nd is my laptop which only shows the past 21 days of e-mails. I've tried all the suggestions you gave me along with comparing all the settings between each computer and still no success. PLEASE, CAN ANYONE HELP ME, I'M TRYING TO GET MY INBOX TO SHOW ALL RECEIVED E-MAILS, UNTIL I DELETE THEM MYSELF.

re : I have 2 computers at home, the 1st a desktop running Windows7 which shows all e-mails I've received from day one going back to 2013 in the inbox, and the 2nd is my laptop which only shows the past 21 days of e-mails.

Q1: On the computer you describe as '1st a desktop running Windows7 ' What type of mail account have you created pop or imap?

Q2: On computer you describe as ' 2nd is my laptop which only shows the past 21 days of e-mails.' what type of account have you created pop or imap?

Q3: When you logon to your webmail account using a browser, how many emails do you see in the 'Inbox' ? Do you only have emails from the past eg: 21 days or does your webmail Inbox really have all emails going back to 2013?

If the webmail account viewed via a browser only has 21 days worth in the server Inbox and the laptop account uses IMAP then it will only show what is on server.

If the desktop uses POP then it will download what is in server Inbox. If you have settings to leave message on server, then message is left on server, so laptop using IMAP will see it. But if you have the pop account set up to delete after x days or to delete anything you delete in pop account then those deleted emails will get removed from server, so IMAP account on laptop will not see them.

If you have another means of accessing server eg: Phone and it access using pop then it could also be downloading and deleting off server.