I bought a laptop online in Korea and it arrived defective?

You have real consumer rights here, and they apply to foreigners the same as to Koreans, so an all-sales-final notice does not override the law for a defective product. Korea's e-commerce law gives strong protections: for online purchases there is generally a right to withdraw within seven days of receipt, and for goods that are defective or different from what was advertised, that right extends to within three months of delivery, or 30 days from when you discovered or could have discovered the problem. A seller cannot simply waive these with a no-refunds notice. First, demand a refund or exchange in writing, citing the defect. If the seller refuses, escalate: if you bought through a platform like Coupang, Gmarket, Naver, or 11st, use the platform's dispute process, since they often side with buyers on defective goods. If that fails, file with the Korea Consumer Agency or call the 1372 consumer hotline for mediation, and for card payments you can request a payment dispute with your card company. Keep the listing screenshot, order record, photos of the defect, and all messages; with that evidence, defective-goods cases usually resolve in the buyer's favor.