On an email already sent, how can I tell if was opened?

[SAD]

I laread sent an email, and did not mark it to notify me when opened.

Is there a way I can tell if the party I sent the email to, has opened that
email?

I am using Microsoft Outlook.

 

[Dirk Goldgar]

I laread sent an email, and did not mark it to notify me when opened.

Is there a way I can tell if the party I sent the email to, has
opened that email?

Only by phoning and asking them.