If endpoints are configured to be communicating with the console you can update the license file on the endpoints using the update license file function on the console. If an endpoint is configured to communicate with the Console then they should still be in communication with the Console even after the license expires.
Admin>Endpoint Updates>License Updates
If your license on the clients has already expired and the endpoints are not configured to communicate with the console, you will need to copy a new license to the clients, replacing the current one on the clients. The file must be named identityfinder.lic and must be placed in the same folder with the Identity Finder application (IdentityFinder.exe) on a Windows machine.
For example on a 32 bit machine with version 10, the default is the following however it may be different due to your customized install:
On a 64 bit machine the default is:
C:\Program Files (x86)\Spirion\identityfinder.lic
On a Mac Client machine the license file is at the following location:
/Library/Application Support/Identity Finder/identityfinder.lic
On a Linux Client machine the license file is at the following location: