Pack1.part3.rar

Many multipart archives are password-protected. If prompted, the password you enter for Part 1 will apply to the entire set.

Platforms like email or certain cloud storage services have strict file size caps. Pack1.part3.rar

This usually means one of the parts was downloaded incorrectly. Use the "Test" function in your archiver to find out which specific part is broken so you can re-download only that one. Many multipart archives are password-protected

Right-click on Part 1 ( Pack1.part1.rar ) and select "Extract Here" or "Extract to Pack1/". Pack1.part3.rar

If the extraction stops and asks for Pack1.part4.rar , it means the creator made a fourth part you haven't downloaded yet.