KeyAccess Ks-240 dialogue box popping up while launching the webstorm. I have a valid key, however am not sure where to paste to get rid of the keyaccess problem. Please help me.

Please see http://www.sassafras.com/docs51/messages.htm#Heading4:

KS-240 The network KeyServer, which is required by KeyServer controlled programs, cannot grant you permission to run this program because you are not a preferred user.

Some users may be designated by the KeyServer administrator as preferred users of a Control, other users are classified as common. If a common user launches a KeyServer-controlled program that is disabled to common users, the license is denied and this message is posted. There is usually nothing the user can do to gain access to the program, but the administrator can either enable the Control for common users or make the user preferred.

I don't think this can be resolved on our end... Please try contacting your KeyServer administrator