You cannot open .part2.rar by itself. You must have all other matching parts in the exact same folder (e.g., CDRL-030.part1.rar , CDRL-030.part2.rar , CDRL-030.part3.rar ).
The prefix heavily implies that this file belongs to a corporate or government project, likely involving engineering, defense, or aerospace contracting. CDRL-030.part2.rar
Depending on the contract, files named like this often contain: Technical manuals, system software, or source code. Risk management or continuity of operations plans. Financial assessments or milestone engineering drawings. You cannot open
Because this file ends in , it is a split archive . A large file or folder was chopped into smaller pieces to make it easier to send or download. To open it successfully, follow these steps: Depending on the contract, files named like this
You need a specialized extraction tool. For Windows, use WinRAR or the free alternative 7-Zip . For Mac, use The Unarchiver .
Are you missing the other parts (like part 1) of the archive?
Contract Data Requirements List (CDRL) Best Practices - DTIC