Downloading TREX
You download the most current TREX version from SAP Service Marketplace. You can use the downloaded TREX software package for two purposes:
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You use SAPCAR to extract the downloaded TREX software archives.
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1. Access the SAP Software Distribution Center on SAP Service Marketplace at http://service.sap.com/swdc
2. Navigate to SAP Software Distribution Center → Download → Support Packages and Patches → Entry by Application Group → SAP NetWeaver → SAP NetWeaver → SAP NetWeaver 2007 → Entry by Component→ Search and Classif. (TREX) → TREX 7.10 → <operating_system> (Linux_on_X86_64_64bit/Windows Server_on_x64_64bit) → TREX71_<Revision>.SAR
3. Download the TREX software package from the specified folder on SMP into a temporary folder on your host.
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1. Create a directory <TREX_DOWNLOAD> for the TREX software package.
2. Use SAPCAR to extract the downloaded TREX software archive TREX71_<REVISION>.SAR to the directory.

SAPCAR is installed with each SAP Web AS in the kernel directory. If you do not have access to the currently installed SAPCAR tool, you can download the unpackaged version of the SAPCAR tool at http://service.sap.com/patches → Entry by Application Group → Additional Components → SAPCAR.
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1. Go to the directory in which you have downloaded or copied the archive files:
○ UNIX: cd /<TREX_DOWNLOAD>
○ Windows: cd \<TREX_DOWNLOAD>
2. Start SAPCAR to extract the archive to the current directory:
○ UNIX: <path to SAPCAR>/sapcar –xvf <file_name>.SAR
○ Windows: <path to SAPCAR.EXE>\sapcar.exe –xvf <file_name>.SAR

You can use the option -Rto specify a specific target directory, for instance, sapcar -xvf <SAR_file> -R <target_dir>. Directories in the archive are created as subdirectories of the target directory to retain the directory structure of the archive.