E-mail Recieved in Error

What if you receive an e-mail that you believe was not intended for you? Should you reply asking the sender if then meant to Cc: you in the e-mail? Would it make a difference if the e-mail was Cc:'d or sent directly to you?

If I received an e-mail by Cc: that didn't seem to apply, I would go back and kindly ask the Sender what they would wish for me to do based on their e-mail. This would give them the opportunity to either clarify or let me know I was Cc:'d in error.

They could have just made a mistake in clicking on your e-mail address, but it is always courteous to be sure if any action is expected from your side.

There is a difference if you are in the To: field. When you are included in the To: field this indicates the Sender is requesting your direct comment or reply. Cc: is more of an FYI keeping you informed. If you are Cc:' you only need Reply back if you have something relevant to contribute to the conversation.