After downloading a manual test for offline execution a manual testing license is checked out.
This license remains checked out until the file is checked back in to SilkCentral Test Manager. If this file gets deleted then follow these steps to release the license back into the pool.
On the dashboard screen go to Add Pane and choose Manual Testing Overview. Choose the project for which the file was downloaded. The offline file should be listed.
Click cancel to delete this offline test file association from SilkCentral and release the license back into the pool.