%META:TOPICPARENT{name="ErrorMessagesL"}%
= 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 [[OplmgrNetworking|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 <nop>OpenLink-related processes, most importantly the License Manager, and this error should cease.