Modern versions of macOS (Catalina and later) do not support 32-bit apps, making most of CS5.5 unusable. Better (and Safer) Alternatives
Adobe CS5.5 Master Collection requires a valid license key to activate and use the software. A license key is a unique code provided by Adobe or an authorized reseller to unlock the software.
Adobe Creative Suite 5.5 was a powerhouse of its era, but today, "keygens" (key generators) are primarily used as bait by cybercriminals to compromise user systems. The Dangers of Using a Keygen