because it happens that people forget/remember their old login and then switch account and I didn't know if you are in the same position as him or not. What I suggested doesn't have anything to do with the emails sent. keronkkumar said the accounts are compromised and the hacker has access to them. I suggested he checked who has logged into the account, rather than to look who sent emails. The x-originating-ip would not be there.
GMAIL, for example, does not show the x-originating-ip header when you send a mail, neither does hotmail or, probably, most of the big email providers.
I became aware of x-originating-ip from using Yahoo and AOL, and did not realize that other email services operate according to other data standards. I tried a search or something... and wanted to try to understand "Headers".
The forgetting of personal login information is understandable. A registered member should make a personal written record for safe-keeping. I am a separate person from keronkkumar.
---Note also, that password managers can be a problem in case someone forgets either username, password, or both; or even the address of the website. Computer problem making you lose software or installed programs might have meant losing the software which held all the login credentials, so a written record would be needed, for later, after either restoring the computer or setting up new computer and getting back onto the internet.--------------off-topic. This was supposed to be about getting IP from gmail.