this is for cs4
#1 In Terminal type following: sudo dscacheutil -flushcache
#2 Hit return, enter your admin password when prompted and hit return.
#3 In Terminal type following: sudo rm /Library/Application\ Support/Adobe/Adobe\ PCD/cache/*
#4 Close Terminal.
#5 Go to: http://www.adobe.com/support/contact/licensing_download_eula.html
#6 Download the licensing repair tool (at the bottom of the page).
#7 Run it, and follow on screen instructions, quit when done.
#8 Instal "Little Snitch" from www.obdev.at
#9 Restart your Mac
#10 Little Snitch will ask for permissions, allow most but when you notice an adobe application ALWAYS DENY!
#11 Run a CS4 application, you will now see the activation window, follow on screen instructions.
#12 When it ask for serial use one of following:
#13 Complete the activation stuff, and deny all connections from Adobe applications.
Everything should be working now, hope this helps.