CS5.5 recently started failing activations when a program from the suite was started up. All that comes up is a dialog box that states it could not be activated. I've tried it on different networks to eliminate proxy issues, without firewall and anti-virus running, with fresh host files and anything else the support docs suggested. I've tried contacting Adobe support through the chat but they can't seem to help me either. The programs had no issue until Monday afternoon. Uninstalling and re-installing the suite worked for a bit but after 12 hours or so it started failing activation again. I'm hoping someone here can help.
Sign in, activation, or connection errors | CS5.5 and later
For anything beyond that you will have to provide proper system information and other details, which you haven't done.
Mylenium