What should Harinder do after receiving an additional Form W-2?

After receiving an additional Form W-2, Harinder should use Form 1040-X to amend his tax return. This is the correct approach because the additional W-2 indicates that there is new income information that was not included in his original tax return. It is essential to report all income accurately to comply with IRS regulations. By filing an amended return using Form 1040-X, he will ensure that his tax liability is correctly calculated based on the complete information from the new W-2.

An amendment is necessary because the additional income may affect any tax owed or any refund expected. Filing a new Form 1040 immediately is not appropriate because he needs to address the specific changes in his previous return rather than starting over. Similarly, ignoring the new information can lead to potential penalties for underreporting income. Contacting the IRS may not resolve the issue, as they would advise on how to file an amendment rather than handling the matter directly.