returned email

[Ron]

this is probably not a Linux question but I would appreciate
understanding what is happening.  I am receiving two or three emails
every day that are from email programs informing me *my* email to
*username at domainname* was undeliverable.  What is confusing me is
none of these emails were sent by me.  I know none of the intended
recipients and none of them are in my addressbook. Any input would be
appreciated.

Thanks
-- 
Ron
ronb at cogeco.ca