It appears that my email account is sending hundreds of emails to random email addresses. My spam filter indicates several hundred returnd or dameon failure notices every couple of days.

pending on your email service provider &/or email client,
you may be able to mark emails as 'safe' simply by adding them to your actual contact list.
This may prove useful to you: http://onlinegroups.net/blog/2014/02/25/how-to-whitelist-an-email-address

Don't Post Addresses Online- Never post email addresses online such as in message boards, forums or on websites for all to see. Spammers (and Phishers) have automated processes that can 'harvest' these. If you must post it, then disguise the format (e.g. john.smithATgmailDOTcom).
- If you receive a lot of spam, a web search for your email address may reveal whether it is posted anywhere online and you can remove it.
Avoid Common, Guessable Formats- The more complicated your email address, the less likely it will become a target for spam. Spammers use software that trys to guess email addresses and a commonly used format such as [email protected] will be a greater target of attack than [email protected].
- Obviously, the trade-off is that your email address will not be quite as memorable or look as nice.
Limit Sharing of Addresses- The more you share your email address, the more spam you will receive, it is that simple.
- Never share your primary personal or work email addresses with those you don't know or trust.
Use 'Disposable' Addresses- Many stores and online services request email addresses for things like account registration, mailing lists and discounts. Set up an email address specifically for these cases, so you do not have to use your primary personal or work email address.
- When spam becomes an issue for this additional email address, simply dispose of it and set up a new one. Services such as Gmail allow you to check and send from different email addresses in one place, facilitating easy management of multiple addresses.
No Email Based Screen Names- If you participate in message boards, chatrooms, Twitter or similar where you display an on-screen name, don't use your email address before the @ sign as the screen name.
- Spammers will often take screen names and add common email endings such as @gmail.com, @yahoo.com and @hotmail.com, in order to guess legitimate email addresses.
Delete without Opening- It is often obvious from the subject line that an email is spam.
- Simply add the sender to your spam filter and delete the email without even opening it. If you do not open it, there is no possibility of the spammer being informed that your email account is active.
Disable Automatic Content Downloads
- Automatically downloading images or other dynamic content in emails might make them look nice, but can reveal to the spammer that your email account is active.
- As a minimum, turn off automatic image downloads in your emails until you are sure the email is trusted and not spam or a phishing email. Specifying to read messages in plain text only will add a further level of security, as all dynamic content will be blocked from download.
Don't Forward Spam- Be wary of emails from anyone asking you to forward the email on, such as petition, chain or joke emails. By forwarding these emails, you are effectively spamming others.
- In addition, these emails are used by spammers to obtain legitimate email addresses for spamming, as they contain the email address of everyone who has forwarded the message along with the addresses of everyone each person forwarded it to.
Never Reply or Click the Links- Clicking links, including the ubiquitous 'unsubscribe' link, in spam emails or replying to spam, will confirm to the spammer that your email account is active, resulting in more spam being received. It may also direct you to a website that contains malware.
- Never reply to spam and avoid clicking links in spam emails. Only click the 'unsubscribe' link for marketing emails you remember signing up for.
Never Purchase anything from Spam- Don't fall for products or services advertised in spam emails, no matter how good they may sound. If it sounds too good to be true, it usually is.
- Buying something advertised in spam only supports the case for spamming and will likely increase the amount of spam you receive, as the spammers now know you are willing to buy.
Avoid Opting In- When purchasing or registering something online, there are usually one or more checkboxes allowing you to opt out of marketing communications or sharing of your information with other 'partners'. If you opt in, you may be opting in to a lot of future spam.
- Always read the opt-out messages with care, as these are cleverly worded to get you to opt-in. Some of them require either selection or de-selection to opt out, whilst others require a mix of selection and de-selection to fully opt out!
Read Privacy Policies- Always read the website's privacy policy before purchasing products or registering your details for software or services online.
- Understand how your email address may be used and whether they can share or sell it to other third parties, who could be spammers.
Use a Spam filter- Activate Phishing and Spam filters on your email account and in your Internet browser to help ensure you avoid receiving spam in the first place.
- Most reputable email service providers will have spam filters that you can turn on, some of which allow very granular policies to be set.
Report Spam- Report spam that does slip through the net to your email service provider or your company, as applicable.
- This will add the sender to their spam filters, identify whether spam filter policies need to be updated and will block future spam from that sender appearing in your inbox again. Reporting spam can also result in the spammer being identified and criminally prosecuted.
Keep Anti-Virus Software Updated- Ensure your anti-virus software is kept up to date and download the latest signatures on a daily basis.
- A lot of malware is designed to access your email contacts and send spam or malware to them from your email account without you even realising.
If it all gets too much...- Finally, if the amount of spam becomes too much to control, you may simply have to start again and obtain a new email address.
- Monitor the old email account in parallel to ensure that all legitimate contacts have your new email address, then delete the old one.

IN YOUR SPAM FOLDER SELECT THE EMAIL WHICH IS NOT SPAM AND CLICK THE "NOT SPAM" BUTTON AT THE TOP. THIS WILL "TRAIN" YOUR SPAM FILTER. LIKEWISE, IN MAIL, IDENTIFY SPAM AND CLICK THE SPAM BUTTON TO RETRAIN. AFTER A WHILE THIS WILL NOT BE NECESSARY

Visit Spamcop.net. Excellent spam filtering service for $30 / year...

You cant stop spam easily, it will always come and will be getting worse soon.To help stop spam don't give out your email and turn spam blockers on

If people in your address book are getting email from you that you didn't send, either your computer or your account has been hacked; you need to scan your computer for viruses and change your email password.

If only you are getting emails you didn't send, marked returned unable to deliver, a spammer is hiding his email address and making the email look like it came from you to get past Yahoo's spam filter. Report these messages as spam. If you keep getting them, you may need to set up a filter.

Have him set up his own email account for free with hot mail or gmail. You can select these emails and send them to the spam file. Your email server may allow you to call them spam and filter them out.

for your reference, you should never post your email address in a forum post because Spam bots randomly check forums for email addresses and you will end up getting way more spam email than you want.
To help you with your login problem, Just try to log in facebook and when it fails, click Forgot Password, which it will send you a confirmation email to reset your password.

Unfortunately, Yahoo does not have the option to only receive emails from people in your contacts or address book. The more websites you click on, the more "cookies" will be placed in your browser by ad trackers, and the more "spam" or junk mail you will receive. Try going into your internet options and disabling third party cookies, or you could open a hotmail (MSN) account where you have the option of only receiving emails from those people in your address book.

Hi,

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