You cannot successfully apply an Endpoint Protection license or update your licenses.
"The specified .slf file could not be applied...."
This issue has multiple causes. This article describes two possible solutions, and provides links to support articles that describe other solutions.
The error can occur if you try to activate a license from the remote Java console.
You may also encounter this if you either save the file incorrectly or open it improperly to inspect it. Either action may change the checksum of the file and make it unusable.
If you encounter this error when you try to activate a license from the remote Java console, activate the license from the local management console instead.
Make sure that you have downloaded and saved the license file properly. Do not open the file for any reason, work with a copy if needed.
For more information about properly obtaining a license file, see the following article: