Malware mailing spam

[PenelopeWakeham]

Hi,

I am sending out loads of spam mail to everyone in my contact.
I did an avast scan.
I have completed a scan with Malwarebytes as advised but nothing was found.
A search on the forum seems to suggest that the malware is not on my computer but as I have logged on only twice in the last week (illness) and the undelivered mail corresponds with the days I downloaded mail (from BTYahoo) I sort of feel the problem is on my computer somewhere.

Can anyone suggest where I look next?  I must be annoying a lot of people I can ill afford to annoy.  Some of it must be getting through!
Thanks muchly
Penelope

[DavidR]

How do you know you are sending it out ?
Just because people say you are doesn't mean it is the case.

Is this an webmail account with email sent and read vial your browser or is your email sent and received through an email program ?
If the latter, what is your email program ?

[PenelopeWakeham]

Hi David,
I am getting loads of returned mail and 2 people have emailed to tell me they are receiving spam from me.

I download mail from BT Yahoo to Mozilla Thunderbird. 

I haven't opened Thunderbird this morning yet - hoping to clear the thing before I do.  I can see on my iPad and phone though, I have another crop of non delivered mail from logging on yesterday.

Hope that helps.
Regards,
Penelope

[essexboy]

Change your web mail password, generally this problem indicates a hacked webmail

[DavidR]

Hi David,
I am getting loads of returned mail and 2 people have emailed to tell me they are receiving spam from me.

I download mail from BT Yahoo to Mozilla Thunderbird. 
<snip>
Regards,
Penelope

Aside from what essexboy said, sensible precaution.

An other thing it could be is that someone that you communicate with has an infected system and their email address book has been harvested. Now your email is likely to be on a spam list and it isn't just spam that you get, these lists also use your email as the from email address.

I would also advise you to increase the Mail Shield > Settings > Sensitivity, Heuristics to High. This may be able to detect if spam is actually being sent from your system, rather than from your webmail account (as essexboy suspects).

[PenelopeWakeham]

Thanks both,
I've changed my password.  While in BT webmail I deleted the undelivered mail and then I noticed the draft folder had tons of mail of the same sort as the spam mail.
I assume it sits there and is mailed when I download to Thunderbird?

My husband received one of them and so did a distant cousin.  There is no reason for either of them to have the others address in their contacts.  The common denominator is me.

Thanks for your help - lets hope that's fixed it. 

I will increase mail protection.  If there is anything else I should do, please let me know.  For the moment, fingers crossed.
Regards,
Penelope

[DavidR]

You're welcome.

I think that is it for the time being, but monitor the situation for a while and report back if it continues or you get an alert by avast on email being sent from your system or from webmail.

If the problem continues it may be necessary to run some analysis tools and essexboy can help with that side of it.