Sounds like your experience of having your email used for nafarious reasons is worse than mine. I changed my password and have not had a problem with it in the last 6 months. I'm thinking that fixed it, but I'm still watching it closely. I didn't lose any info.. Just embarrassed that the spam got sent out from my address.
I think they got my password from me signing in on a phishing, (fake), sign in page that looked just like the Yahoo page. Whenever I'm asked to sign in, or re-sign in, to a website now, I open a new browser window and start fresh so I know it's not a phishing page. They are getting sneekier all the time.
The same thing happened to my daughter last year. All she did was get a new email and didn't close her old account. I told her yesterday to go back and close the account with Yahoo so I, (and everyone else on her old contact list), would stop getting the spam mail in our inboxes.
As far as dangers, any sensitive info. on your email account could be compromised and used to possibly hurt you. Account numbers and such. A virus could be slipped into your account and infect your computer. Who knows!? So far as I can tell, changing the password on my account has stopped the one issue I had. Which was using my account to launch spam mail.
Hope you have the same results as I have so far.....GOOD LUCK!!
