If you are using Astah Community or Astah UML, you must have many greyed-out menu on Main Menu as the left in the figure below.



























This is to indicate users the features or diagram types that other editions support, however this could be just an obstacle if you are familiar with all the features and satisfied with what you have already. Such in case, you can get rid of them and make it clean by:

1) Go to [Tool] - [System Properties] - [Management View]
2) Check off the option, "Show main menus of Astah UML, Professional (Restart Astah)", click [Apply] - [OK]








3) Restart Astah, the greyed-out menu no longer appears.

Cheers,
SJ