What kind of warranty does this product come with, and what does it cover in terms of support and repairs?

The product comes with a 3-year limited warranty.

Questions & Answers: WD 4TB My Passport Portable External Hard Drive HDD with Password Protection and auto Backup Software, White - WDBPKJ0040BWT-WESN

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WD 4TB My Passport Portable External Hard Drive HDD with Password Protection and auto Backup Software, White - WDBPKJ0040BWT-WESN

Slim Design
Software for device management and backup with password protection. (Download and installation required. Terms and conditions apply. User account registration may be required.)
256-bit AES hardware encryption
SuperSpeed USB port (5Gbps); USB 2.0 compatible
3-year limited warranty