Citrix::Metaframe::Terminal Services License
Microsoft Terminal Server is licensed per seat which means every computer you access a TS from the internet burns a license. There's some "timeout" that allows a license to be released after a period of time. There is also some over the internet MS Licensing service changes that will release it.
To skip this for a temporary fix, create a .REG file from the info below and merge it on the client machine: