Firstly confirm that your Internet is working by visiting a live web page such as http://www.bbc.com/news/ where the current date and time are shown.
Are you using a Microsoft POP mail program? These typically are Windows Mail. Windows Live Mail and Office Outlook. Email downloaded to these programs lives on your machine and can be read even when the Internet is unavailable. The shortcut key "F5" on the top row of the keyboard can be used to do repeat send and receive operations.
If your Internet is working and you have not changed any email settings then it is most likely that your mail provider is doing server maintenance or has an authentication problem which is often sorted within 24/48 hours. The good news is that there is sometimes a workaround...
Simply visit your ISP's home page and look for an "Email" login. When POP mail fails web mail may still be available. The easiest way is to Google the appropriate phrase such as "BT Mail", "Sky Mail" or "TalkTalk Mail" etc. and ensure you are on a genuine page.
A useful link where any email can be logged onto is the free "mail2web" facility at http://mail2web.com/
Webmail does require you to remember and enter your email address and CORRECT password. Did you know 80% of customers don't remember or wrongly remember their email address and password combination!
Beware some email hosting companies will lock you out after three failed password attempts. Look for the forgotten password link and complete the security details you gave when you signed up.
In the meantime it only takes a few minutes to open a new free email accounts with Microsoft or Google. This will enable you to keep in touch with friends and customers until the problem is resolved which in many cases it will be within 24 hours.
There are instances of hard drive glitches or memory errors, also of viruses or password poisoning that can cause POP email problems and if you believe you may be a victim I can carry out appropriate tests for you.
You may even have become a victim of email account theft. In 2014 Yahoo, who used to run BT's mail service, disclosed thousands of email address and password combinations. I know of thirteen families in this area who fell foul of this.
DON'T FALL VICTIM TO MASS MAILING WORMS!!!
Scenario: You receive an email. (This is easier to fall for if it comes from someone you know who has themselves been hit.) The email has an attachment or a link which you click on and in the blink of an eye your PC is infected.
Make it a rule to always SAVE not OPEN an attachment and save it to a place you can find it such as the Desktop or Documents folder. Next make sure your anti virus program is up to date and if so navigate to the saved attachment and RIGHT CLICK it and from the context box that opens choose SCAN.
Even if your ISP says it scanned your mail, don't trust them and still carry out your own scan. Many types of file extension can contain viruses including: DOC, XLS and especially ZIP files and of course EXE files which execute the attacker's command.
Some people are plain unlucky and are infected by a FIRST DAY VIRUS. That's a new virus that your anti virus program doesn't yet know about and probably won't be able to deal with. If such a virus has the ability to ZERO your hard drive you will be so glad that you BACKED UP ALL YOUR VALUABLE STUFF to external media such as a CD, memory stick, external hard drive or cloud storage which can be obtained free from a variety of sources.
Ever wondered what a data centre looks like? These are some of the data
servers inside FACEBOOK'S NEW DATA CENTRE.
(I do not own
this image which appears to be freely circulating on the Internet.)