[WPT3.0] WPTdriver causing OS reboot


My WPT 3.0 installation is running fine now but I noticed frequent system reboot. I had a look to Windows event viewer and found that these reboots are caused by wptdriver, here is the windows event details:

C:\webpagetest_3.0\wptdriver.exe (PAR-WVHAC)
Legacy API shutdown

I’ve googled for “Legacy API shutdown” and found this could be caused by many different software. It isn’t specific to WPT but it looks that the reboot is caused by WPT and something else.

Does anybody experience a similar issue with WPT 3.0 ?


Is the display unlocked and visible (and power management set to not turn it off)? The agent will automatically reboot the machine if it can’t get screen shots (used to do it immediately, recently made a change to allow for a 10-minute grace period).

That is good to know. I think I configured it correctly:


Is there anything else to do?

FYI, my windows host is running as a VM.

Hi Patrick,

I am also seeing the exact behavior.

Is this setting configurable? or can we make this setting configurable? So that we can tell agent not to restart the machine even if it does not see the screen. Sometimes I do run agent on my devbox while debugging. And if I lock my box for sometime, and try to log in to the box, it has already initiated the reboot of the machine and this is very annoying. So if we can make this setting configurable that would be great.