(often found as CRU March 2020 by BWC.7z ) is a compressed archive containing a community-developed Root Certificate Update for legacy Windows operating systems, primarily Windows XP and Windows 2000. It was created by a well-known Japanese developer in the legacy Windows community who goes by the handle BlackWingCat (BWC). Purpose and Utility
: The primary certificate database file (often renamed to .cab during the installation process).
: Contains the necessary binaries and support files to execute the update. Security and Usage BWC.7z
The archive typically includes the following files used for the manual update process:
: Always verify the source. BlackWingCat typically publishes updates on his official blog (usually in Japanese). (often found as CRU March 2020 by BWC
: A batch script used to automate the installation of the certificates into the system registry.
Because these files are hosted on third-party mirrors like or archived on the Internet Archive , users should exercise caution: : Contains the necessary binaries and support files
The BWC.7z file contains updated certificate stores that allow these legacy systems to recognize modern SSL/TLS certificates, effectively extending the browsing life of the OS. Key Components