Because the software requires an internet connection to verify your license against TreeCardGames' server. When you enter your code, the software "calls home" to the support server to confirm the key is valid and not blacklisted.
If you’ve lost your code or changed your email, you can request it again by filling out the Activation Code Request Form on the support site. mahjong suite support activation code
Alternatively, you can use the keyboard shortcut while the program is open. Because the software requires an internet connection to
