Got this, this morning in my Junk Mail. I have never heard of the IRS contacting you via e-mail

Did not open atachments and will not, If IRS wants something from me they will have to do it by mail and not e-mail.
It just goes to show you what scammers will do

Department of Treasury Internal Revenue Source
Important information about your tax return
We are unable to process your tax return
We recived your tax return. However, we are unable to process the return as field.
Our records indicate that the person identifiedas the primary taxpayer or spouse on the tax return did not provided all the required documents shown on the tax form. Our records are based on information received from the Social Security Administration.
Based on this information, the tax account for the individual has been locked
What you need to do
Print out the attached notification and list of missing documents, fill it in, add the documents and send the following information to the adress shown in the attached notification.
List of required documents:
1. A copy of this letter
2. Notification letter
3. A photocopy of valid U.S. Federal or State Government issued identification.
Keep this notice for your records. If you need assistance, please don't hesitate to contact us