If your W-2 doesn't have a Box D (Control Number), you can leave it blank. The IRS doesn't care what's in Box D because its use by payroll departments is optional.
If you're trying to import your W-2 with a blank Box D, click skip import and then manually enter your W-2.
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).
Please see FAQ below for more information.
https://ttlc.intuit.com/replies/4417180
