I was using a 10 license key and tried to upgrade to an unlimited license.

I did the follwoing:
 1- Re-issue license (unlimited) from Centova.com
 2- Edited the file /usr/local/centovacast/etc/license/license.key/ and deleted what was there and entered the new licesne key.
 3- restarted Centovacast

Now the control panel shows Total Streams - 10 / UNL

However when I try to add another station, I get the error code:
Account could not be created: The target server has reached its licensed limit of 10 account(s); please upgrade your license if you require additional accounts.

What's up ?

The license key should go into /usr/local/centovacast/etc/license.conf

Oops .. you are correct ..  I put it in:
/usr/local/centovacast/etc/license.conf

then restarted Centovast and still get:

Account could not be created: The target server has reached its licensed limit of 10 account(s); please upgrade your license if you require additional accounts.

I went in and re-issued the unlimited license.

Thanks for the help.  What's next ?

It shows 10 (UNL) on my Control Panel

Old thread, but if you're still wondering, you need to restart Centova Cast after changing your license key.