If it asks for a password, check the site where you found the link (usually ziperto.com ).
Right-click only Part 1 and select "Extract Here." The software will automatically "reach out" to Part 2 and Part 3 to pull the full .nsp file out. You do not need to extract Part 2 individually. 4. Troubleshooting OL2-NSwTcH-[BASE]-NSP-(eShop)-Ziperto.part2.rar
This usually means one of the parts downloaded with a tiny bit of corrupted data. Try deleting Part 2 and re-downloading it. If it asks for a password, check the