Hello, I would like to know how to report a foreign interest income without a FEIN. I keep seeing that writting 00-000000 or any place holder will not work.

Leave the field blank.  Don't enter any numbers.  

• Enter the interest income in box 1. 
• If you paid any foreign taxes on the interest income, enter the amount in box 6 of the online Form 1099-INT.

To enter the foreign interest income, see Where do I enter Form 1099-INT?

Thank you, but when I review my return at the end. Turbotax flags this as an error.

Try to scroll down that page and click Continue to skip it - that message should not prevent e-file.