KVM Remote Control Connects and then disconnects immediately

KVM Remote Control Connects and then disconnects immediately

I am using the latest version of Mesh Commander and I can connect to my system remotely and view all the information available about the system.  I am able to remotely control the system as well (i.e. power cycle, power off, power on, boot to bios, etc.).

I am able to use KVM Remote Control during boot up and to view the BIOS.  Once Windows 10 loads, I immediately lose the remote control connection.  When I try to re-establish a KVM Remote Control connection, it connects and then immediately disconnects.

I am able to remotely connect to the Windows 10 session using regular VNC server/viewer.


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Hey Erik,

Not a lot of details, but the behavior suggests a Handoff between the Hardware and OS. I would start with updating the wireless drivers and potentially the FW/BIOS.

If that doesn't work, please use acuconfig.exe and perform a system discovery. Please email me the resultant fie.

The commandline string will be acuconfig.exe systemdiscovery


Download location




Sorry for not providing more details.  Here is some more information about my system build.

Motherboard: ASUS Q170M-C with BIOS Version 3405
CPU: Intel Core i7-7700
RAM: 2 x Kingston DDR4 Part # KHX2133C14/8G = 16 GBs total
System Drive: Samsung SSD 850 EVO 500 GB
Storage Drive: Seagate ST6000DM001

I have installed Windows 10 Professional with all updates and patches
All drivers and hardware software are current and up to date as of 9/8/2017

The system was built in my home in Missouri.  It was originally hooked up to a standard Gateway monitor using DVI connector.  All Intel vPro, AMT, and KVM features were functioning without any problems using Mesh Commander.

The computer was transported to New York and hooked up to 65 inch Samsung 4K TV/Monitor.  The resolution was changed to support 4K  and is currently set to 3840 x 2160 (Recommended) in Windows Settings.

It was suggested that I try a remote desktop connection using Real VNC +.  I downloaded the trial version and attempted to make a connection and received the following error...

     Error: 0x80862505: Viewer requested an invalid pixel format

According to a KB article that I found here (https://support.realvnc.com/Knowledgebase/Article/View/515/10/error-0x80862505-viewer-requested-an-invalid-pixel-format)... This is due to the AMT computer's lack of support for certain pixel formats (anything over 16-bit depth) - the error is from AMT, and is listed in Intel's docs as: "The combination of bytes per pixel and color depth was not valid."

The VNC Viewer Plus pixel format is valid, but as there is no mechanism to specify pixel formats server-side, occasionally VNC Viewer Plus might select a pixel format that is not supported. In VNC Viewer Plus, try turning off Options > Adapt to network speed and choosing instead an option between best compression and best quality from the slider.

I found that in Mesh Commander, when changing the Remote Desktop Settings to RLE8 or RAW8, I was able to connect without any issues to my system.  Using any other settings resulted in the issues described in my original post.


Best Reply

Hi. Sorry for the delayed reply. I think what is going on is that Intel AMT has a maximum KVM buffer size of 8 megabytes. So, for a 4k display at 2 bytes-per-pixel, it goes over the buffer. At 1 byte-per-pixel, it fits and so, works correctly. The only workaround for this is to use a software KVM solution when the OS is up and use hardware-KVM for other times.

I am working on MeshCentral2 that supports both software and hardware KVM, so it's easy to switch between the two and software KVM will supports 4k. Of course, many other software solutions also exists.

Hope it helps,

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