The sytems updates have been automatically installed on few TSPlus servers. This created few remote access problems.
KB2984972 , KB2973501 , KB2984976 patches are to blame. The problem could be solved by uninstalling updates or upgrading TsPlus to its newest version (paid support required)..
We recommend automatic updates only and manual server patching. We can react faster and have less stressing mornings ;).
