Com-port not responding

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Com-port not responding

Sometimes when you run the Com-ports are not are forwarding. It helps to restart the program several times.
And sometimes it happens that in the Device Manager, the device appears ISF cart question mark (unrecognized device), and only helps restart the server. Is there any possibility not to restart the server, and only the service? then what service?

What hardware is your server?

What hardware is your server? What is your serial device....FTDI?

sorry not ISF -> USB

sorry not ISF -> USB

OK but what is your server

OK but what is your server device? A pi? a custom pcb? a ubuntu desktop etc?

Windows server 2008 R2

Windows server 2008 R2

OK well anyway thats the

OK well anyway thats the client but to restart the service on the client you use

net stop vhclient
net start vhclient

however it shouldnt jam with the COM port, what are you ping times? Are they consistent or sometimes large > 3000ms?

Vhui64.exe not running as a

Vhui64.exe not running as a service, as well as a program.
Ping <1mc
we LAN

OK, ping times should be fine

OK, ping times should be fine. You can only restart the server (e.g sudo pkill vhusbdarm;sudo ./vhusbdarm -b)

These commands are executed

These commands are executed on the VH server ? After all, we have a problem on the VH client side (windows server)

You said "stop the service"

You said "stop the service" in the first post, then you said the the client is "not running as a service" i dont know what you are asking? Please explain the problem again.

in our organization, we have

in our organization, we have the following structure:
We have a thin station on Linux. vhui64 Server part installed on thin station. We connect COM to USB adapter in thin station
This thin station connects via free RDP to Windows terminal server. Vhui Client installed on this Server. When we start vhui client on terminal server and customize him, we have new created Com port . And user on terminal server work correctly with this Com port.
Sometime we have a problem with Vhui client. Vhui client don’t create Com port when we start him. And sometime when we stop vhui client on our server created Com port don’t uninstalling.

sorry, I do not know much

sorry, I do not know much English.

Ok thanks for the information

Ok thanks for the information thats much clearer now

I have a feeling there are too many libraries between virtualhere and rdp and somewhere along the line there is some state machine problem or an error or event not being propagated through correctly.

Ideally what needs to happen is i need to write a library called "virtualhere" for this

then i can be sure that the protocol is being correctly implemented or at least error conditions are correctly passed through.

Unfortunately i havent yet written that, it is on my todo list

If the com port stops working i would first remove and re-insert the usb serial adapter into the client and see if that unlocks the jam. That is the only way to do it without restarting the client.

Hong Nguyen
USB to COM of BrainBoxs US-101 doesn't work

I got the problem as bellow:
- USB to COM: with driver: USB-SERIAL CH340 can work. but:
- USB to COM come from BrainBoxes US-101 [USB 1XRS232 ] doesn't work. Everything look normal, except no data transfer
Currently using: Virtual Client 3.6.3, compiled May 19 2016 on Windows 7. Sever program running on raspberry.
Do you have any comments or advice ?

Thanks & Regards
Hong Nguyen

Hong Nguyen
Connection testing by using

Connection testing by using Hyper Terminal.
OS for server: Rasbian

If you just use the brainbox

If you just use the brainbox via virtualhere, in windows bring up "Device Manager" and see if a COM port is listed there for brainbox?

Hong Nguyen
- OS on laptop is Windows 7,

- OS on laptop is Windows 7, 64 bit version.
- Device Manager list the COM port 1 as normal. I can set all parameters communication like baud rate, parity....ect
- USB - CH340 and brainboxes US-101 operate smoothly when direct connect to laptop without problem.
- USB - CH340 work fine on raspberry. But brianboxes doesn't on raspberry without any warning.
Please advises.

Dont know, you will have to

Dont know, you will have to ask brainbox, im not sure, most USB->Serial adapters work e.g FTDI

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