The screen shot captured by urlBlast is a black screen shot

When I configured a private instance of WebPageTest, sometimes the screen shot captured by urlBlaster is a black screen shot.
After some investigations on it, I found the conditions on which the screen shot is black.
I configured an IE test machine on an ec2 machine connected by Remote Desktop Connection on a Windows 7 OS. Only when Remote Desktop Connection is activated (I mean, not minimized or closed), the function of capturing screen shots works fine. Otherwise, the screen shot captured by urlBlast is black.
I’ve googled about this issue, but I didn’t find any valuable suggestions.
Did you have such troubles? If you did, how did you solve this problem?

It’s probably not highlighted enough in the configuration docs (I’ll see about bolding it):

Reboot the instance instead of disconnecting and it should be fine (alt-f4 will bring up the shutdown dialog when you are connected over RDP).



Yes, I’ve rebooted the instance. If the Remote Desktop Connection Window is activated, the function of capturing screen shot works fine. But if the Remote Connection Window is closed or minimized, the function doesn’t work. I don’t know the reason.

Right. Reboot the instance and don’t connect to it. Screen shots (and video) should work just fine. It’s the act of connecting the RDP session that puts it into a bad state.

EVERY time you connect a RDP terminal you need to reboot the instance. The instances are configured to automatically log into the desktop when they start up and the screen shots will work. When you RDP to an agent the desktop gets locked and the screen shots depend on the RDP session.

Thanks Pat.
After I rebooted the instance and didn’t connect it with the Remote Desktop Connection, I tried the webpagetest private instance, the function of capturing the screen shot worked fine.

Hi Patrick.

I have the same issue. In my tests the resulting screenshot are Black.

The problem is that until I connect to the remote server the test can’t start (I see the dummynet prompt blocked when I connect), but if I connect to the remote server the screenshot are black.

How can I solve this issue?