Thanks for using TurboTax
A Control Number (Box D) is used by many payroll
departments to uniquely identify a W-2 in their system. If your W-2
doesn't have one, it's no big deal – you can simply leave it blank.
If
you get errors when attempting to e-file with an empty Box D, just
enter any number in this
format: 5 digits, space, 5 digits (for example,
12345 67890).
The IRS doesn't care what's in Box D because its use by
payroll departments is optional.
Now, if you're trying to
import your W-2 and you're persistently being asked to enter something in Box D, click
skip import to get past this screen and manually enter your W-2 (which should only take a few minutes anyway).
Related Thread:
https://ttlc.intuit.com/questions/2655867-box-d-matches-what-s-the-problem?jump_to=answer_4421994Hope this helps