11 Troubleshooting
the COM server might experience an internal error and subsequently other processes
fail to initialize it. In these situations, it is recommended to use the Windows task
manager to kill the process
VBoxSVC.exe
.
11.4.2 CD/DVD changes not recognized
In case you have assigned a physical CD/DVD drive to a guest and the guest does
not notice when the medium changes, make sure that the Windows media change
notification (MCN) feature is not turned off. This is represented by the following key
in the Windows registry:
HKEY_LOCAL_MACHINE\System\CurrentControlSet\Services\Cdrom\Autorun
Certain applications may disable this key against Microsoft’s advice. If it is set to 0,
change it to 1 and reboot your system. VirtualBox relies on Windows notifying it of
media changes.
11.4.3 Sluggish response when using Microsoft RDP client
If connecting to a Virtual Machine via the Microsoft RDP client (called Remote Desktop
Connection), there can be large delays between input (moving the mouse over a menu
is the most obvious situation) and output. This is because this RDP client collects input
for a certain time before sending it to the VRDP server built into VirtualBox.
The interval can be decreased by setting a Windows registry key to smaller values
than the default of 100. The key does not exist initially and must be of type DWORD.
The unit for its values is milliseconds. Values around 20 are suitable for low-bandwidth
connections between the RDP client and server. Values around 4 can be used for a
gigabit Ethernet connection. Generally values below 10 achieve a performance that is
very close to that of the local input devices and screen of the host on which the Virtual
Machine is running.
Depending whether the setting should be changed for an individual user or for the
system, either
HKEY_CURRENT_USER\Software\Microsoft\Terminal Server
Client\Min Send Interval
or
HKEY_LOCAL_MACHINE\Software\Microsoft\Terminal Server
Client\Min Send Interval
can be set appropriately.
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