Around , Adobe officially discontinued support for CS6 and began decommissioning the legacy activation servers.
Upon entering a valid serial number, InDesign CS6 would attempt to validate the license with Adobe’s activation servers. However, if an internet connection was unavailable, the software did not immediately lock the user out. Instead, it granted a 7-day grace period . This allowed creative professionals to continue working on urgent projects (e.g., a magazine layout or newspaper deadline) without interruption, buying them time to find an internet connection. adobe indesign cs6 serial number validation