How To Determine Cause of Black Screen
Seeing GoToMyPC host when in session.
The symptom of a black screen in the GoToMyPC viewer can have several causes.
The simplest test to determine the problem is to click the Tools menu in the GoToMyPC viewer. If all menu options are unavailable (grayed out), then the session is not fully connecting. Network based security (ie. hardware firewalls, content filters) may be blocking or filtering GoToMyPC traffic. In some cases, GoToMyPC may be sending packets that exceed the maximum transmission unit (MTU) threshold for this network. This can be adjusted by a Customer Care agent, but requires a call to support.
If the tools menu is not grayed out, then the GoToMyPC is fully connected and local security on the host is most likely blocking screen capturing. Below is a list of applications known to cause this type of interference: