Error Message: "License is already in use" or "Unable to open a Request Broker license (License is already in use)"

This error has two common causes.

1 - License Manager does not have sufficient access to TCP/IP network communications

Resolution typically requires opening a few ports in the License Manager host's firewall.

2 - Multiple hosts have the same serialized license file

Resolution simply requires that each licensed host have a uniquely serialized license file -- that is, that each serial number is found on only one host. After you've confirmed license file uniqueness, restart all OpenLink-related processes, most importantly the License Manager, and this error should cease.