Windows system error code 6 is:
ERROR_INVALID_HANDLE
6 (0x6)
The handle is invalid
I’m not sure that we’ve seen this particular error before, but in general when there are very unusual errors like this, it typically means that psexec is failing to function properly. The most common cause of psexec failing to function properly like this is due to an anti-virus client or HIPS or other similar security software suite that terminates the process or severs the network connection abruptly before everything completes.