The lack of a Control Number on your W-2 really shouldn't be a problem that prevents you from completing your tax return, and you should still be able to file without one. Not all W-2s have Control Numbers associated with them, or
printed on them. Please allow us to explain, as well as provide you with some solutions.
The W-2, Box D, Control Number, is a code
that identifies your unique Form W-2 document in your employer's records.
This number is assigned by the company's payroll processing software, and is
only needed if attempting to electronically import your W-2 into a tax software
program (like TurboTax). Please note that not all W-2s (or employers)
will necessarily include a Box D number. Your alternative to importing a
W-2 document is to simply input the same information manually. In that case please do not attempt to import your W-2 by other means; if you do, then delete that W-2 entry entirely, and then add your actual W-2 data manually.
The Control Number itself is basically irrelevant to completing your tax return, unless you wish to import your W-2 into TurboTax, you see; and it that one instance it is required. In other words, the W-2 Control Number, whatever it is, will never increase or decrease your actual tax refund (or your amount owed) by a single penny.
If you type in your W-2 manually, rather than importing it electronically, then you should probably not have to enter anything from Box D at all. In fact, you may be be able to simply leave the field blank. The exceptions to that would be if you are attempting to e-file your return and see some sort of W-2 Control Number related error; or if the program insists on a having a Control Number value before allowing you to continue. For those cases, we have a TurboTax FAQ article that can help. I've linked this answer to that FAQ page below.
If you cannot see the entire FAQ article, then please click on the grey button labeled "see entire answer" to expand the section.
I hope this information is useful to your needs; and thanks for asking this question.
https://ttlc.intuit.com/replies/4417180
there is no box D on my W2 and TurboTax will not let me continue
You don't need a Control Number to file your tax return. Type 'w2' in the Search window, then 'Jump to w2'.
Choose 'Add a W2' and type the info from your W-2 in manually.
If you previously tried to download a W-2 unsuccessfully, Delete that entry.
Click the link for more info on How to Add a W-2.