To tell you the truth, I have never seen that phrase. It is more common to say, "Please see the attached file." You could also say, "You will find the attached file." or "You will find the file attached to this email." In my opinion, "please see the attached file" is the most common. It's the phrase that I see the most. "Attachments enclosed" is another way of expressing the same thing. I hope that helps. May God bless you. Post more questions if you want. Me and the other teachers on italki are happy to help you.

I agree with Neil. If I am drafting a formal email that has an attachment, I will begin the email with "attached please find..."

...choose your balance .... sorry, a typo

As Neil says, use it if the message is formal. This is the way I was taught is the correct way to do this...... I use this always that I have an attachment. I have never had anyone ask what it means, so I assume that it is clear....... You will also see many informal things in emails, such as; r u there, pls, u r ..., lol. You can choose you balance of all these things, correct & incorrect, formal & informal as you think appropriate to the email & the audience.

ATTACHED PLEASE FIND THE FILE. - I saw this sentece in our company's old files (ages ago). I think it was quite commonly used in the past. PLEASE FIND THE ATTACHED FILE. - This is the way it is used nowadays.