My most recent employer, a consulting company in the U.S., kept my email inbox open after I left the company. They delegated its use to the person now running that department. I had been at that company for over eight years.
Before leaving the company, I put an out-of-office message on my email inbox so that anyone sending it email would receive a notice to contact someone else at the company.
I'm not the only person to have left that company that has had this same situation occur.
I think the company's logic is that a past customer may email my old email address, and they don't want to risk missing that email. However, it seems to be abusive to me in that colleagues from other companies who might want to contact me may not be aware, and then the communication is obviously not private.
I know that when using a corporate email system one should have no expectation of privacy.
Is it okay for my past employer to do this?
EDIT: I've recently found out that besides reading mail addressed to me at this company email address, the person in control of this email account has also transmitted an "unsubscribe" email from this account to a website I had used to check my son's school grades. I evidently registered my work email account instead of my private email account.