Launching VirtualBox slave not possible

[ELIASSAL]

HI, I have configured correctly Virtualbox plugin, added a cloud to my VB host, test successful.

Then added a slave to connect to which is a windows 2008 R2 machine which has Java 8.

Once I save the configuration, a log starts and machine is started heedlessly (what I want) successfully, I can RDP the machine but slave does not launch correctly as you can notice in the log hereunder, even when I RDP the machine, go to http://myjenkins and try to start it from the VM itself

[VirtualBox] Launching node NetStockTrader
[VirtualBox] Powering up VirtualBoxMachine{host=VirtualBoxHost{url='http://192.168.1.2:18083/', username=''},name='NetStockTrader'}...
[VirtualBox] Lost connection to http://192.168.1.2:18083/, reconnecting
[VirtualBox] Trying to connect to http://192.168.1.2:18083/, user 
[VirtualBox] Creating connection to VirtualBox version 4.3.20
[VirtualBox] Connected to VirtualBox version 4.3.20 on host http://192.168.1.2:18083/
[VirtualBox] node NetStockTrader in state Running
[VirtualBox] node NetStockTrader started
[VirtualBox] Sleep before stage 2 launcher, attempt 1
[VirtualBox] Starting stage 2 launcher (JNLPLauncher)
[VirtualBox] Stage 2 launcher completed
[VirtualBox] Sleep before stage 2 launcher, attempt 2
[VirtualBox] Starting stage 2 launcher (JNLPLauncher)
[VirtualBox] Stage 2 launcher completed
[VirtualBox] Sleep before stage 2 launcher, attempt 3
[VirtualBox] Starting stage 2 launcher (JNLPLauncher)
[VirtualBox] Stage 2 launcher completed
[VirtualBox] Sleep before stage 2 launcher, attempt 4
[VirtualBox] Starting stage 2 launcher (JNLPLauncher)
[VirtualBox] Stage 2 launcher completed
[VirtualBox] Sleep before stage 2 launcher, attempt 5
[VirtualBox] Starting stage 2 launcher (JNLPLauncher)
[VirtualBox] Stage 2 launcher completed
[VirtualBox] Sleep before stage 2 launcher, attempt 6
[VirtualBox] Starting stage 2 launcher (JNLPLauncher)
[VirtualBox] Stage 2 launcher completed

[ELIASSAL]

Hi, can somebody help on this

Thanks