We've had a stable TeamCity install (version 9.0.3 (build 32334)) for some months. It has a single build agent, MSBuild, which is on the same box as TC. Now, without changing any of the configuration the build agent is showing as Disconnected with the Inactivity Reason: "Agent has unregistered".
I've restarted TC and the box a couple of times but it won't connect. I've left it way longer than ten minutes.
The launcher.log file doesn't show anything different to when it connected successfully:
[2016-04-25 15:18:59,318] DEBUG - .buildServer.agent.JavaChooser - Current Java runtime version is 1.7
[2016-04-25 15:18:59,333] DEBUG - dServer.agent.lock.LockManager - Lock file: C:\TeamCity\buildAgent\logs\buildAgent.properties.lock
[2016-04-25 15:18:59,333] DEBUG - dServer.agent.lock.LockManager - Using no lock
[2016-04-25 15:19:02,344] DEBUG - buildServer.agent.LauncherUtil - Deleting C:\TeamCity\buildAgent\update
[2016-04-25 15:19:02,344] DEBUG - buildServer.agent.LauncherUtil - Deleting C:\TeamCity\buildAgent\update
[2016-04-25 15:19:02,344] DEBUG - ldServer.agent.run.AgentRunner - Update folder deleted
[2016-04-25 15:19:02,344] DEBUG - buildServer.agent.LauncherUtil - Deleting C:\TeamCity\buildAgent\backup
[2016-04-25 15:19:02,516] INFO - dServer.agent.run.AgentProcess - Mon Apr 25 15:19:02 BST 2016 ==> Start launch
[2016-04-25 15:19:02,516] DEBUG - .buildServer.agent.JavaChooser - Current Java runtime version is 1.7
[2016-04-25 15:19:02,516] INFO - dServer.agent.run.AgentProcess - Launching agent with command: c:\TeamCity\jre\bin\java -ea -Xmx512m -XX:+HeapDumpOnOutOfMemoryError -Xrs -Dlog4j.configuration=file:../conf/teamcity-agent-log4j.xml -Dteamcity_logs=../logs/ -classpath {etc}
Is there something obvious I am missing?
Thanks
