If you are seeing the Red Alert in the electronic filing steps, Error or Omission: Form W-2G - Winner State Abbreviation, this is indicating you have not entered a state of residency for the taxpayer or spouse on Form W-2G Certain Gambling Winnings, an entry made in the Basic Information section of the Q&A (in the foreign country field) may be causing this Alert.
To address this Alert:
If the previous steps did not solve the issue of the Alert in the filing steps, then it may be possible the foreign country field was also entered on the Form W-2G like it was in the Basic Information section of the Q&A:
Note that any link in the information above is updated each year automatically and will take you to the most recent version of the document at the time it is accessed.