Note that the information about how to place the file in the license folder was dropped in recent versions of docs, that info is available here: Uploading a new license (4.0)
Installation If you've received a new license from Alfresco Sales, then you should have in your possession a file with a name like Customer-EnterpriseTrial-ExpirationDate.lic. This is your Alfresco license file. It must be installed into the Alfresco application before it will take effect.
The procedure may differ slightly depending on which version of Tomcat you are using. If you are not sure which version you have then you can check this by looking at the contents of the RUNNING.txt or README files in the main Tomcat directory.
Generally, versions of Alfresco 3.0 and greater containing a bundled version of Tomcat will use Tomcat 6.0. Previous versions used Tomcat 5.5.
How to install on Tomcat 6.0
Check if the directory <TOMCAT_HOME>/shared/classes/alfresco/extension/license exists. If does not, then create it.
Check the configuration file <TOMCAT_HOME>/conf/catalina.properties contains the line
Create the license directory if it is not already present.
Move the Customer-EnterpriseTrial-ExpirationDate.lic file into this license directory.
Checking that it works
Upon start-up, Alfresco should detect the existence of the Customer-EnterpriseTrial-ExpirationDate.lic file and install your license. The license information should be printed to the Tomcat console and log files. If the license is valid, Alfresco will rename the file to Customer-EnterpriseTrial-ExpirationDate.lic.INSTALLED and begin to utilize the terms of your license immediately.
Should you have any problems with the installation of a license or license extensions, please contact Alfresco Support immediately.