SX-Virtual Link Software Frequently Asked Questions


About SX Virtual Link

SX Virtual Link is software that allows you to connect to USB devices across the network connected to Silex USB Device Servers.

The way it works is that the software emulates a USB connection on the computer, and makes the USB device (such as a printer or a disk drive) connected to the SX Virtual Link enabled device look as if it were directly connected. This makes it easy to connect and share USB devices on the network.

We encourage users to look at the documentation in the Help file by clicking on the '?' (question mark) within the SX Virtual Link utility to find out about all of the features, and it also includes configuration and troubleshooting tips.


What type of devices are supported?

USB devices like inkjet printers, multifunctional devices, printers, scanners, digital cameras, USB memory, card reading drives, hard disk, CD/DVD/MO/disk drives, but also exotic devices like Yamaha mixers (01v96, DM1000, DM2000), USB weather stations, USB sewing machines, USB measuring devices are supported.

Devices that use the isochronous data stream, such as webcams, sound or TV cards, are only supported by the DS-510, DS-520AN, DS-600 or newer devices. Some of these devices may not work due to driver problems or delay over the network. 


Installing SX Virtual Link

If you are having difficulties installing SX Virtual Link, please make sure you have uninstalled any old versions, and make sure you have one of the supported operating systems (Windows XP, Windows Vista, Windows 7 32/64 bit, Mac OS 10.5 or 10.6).

Also check the HELP documentation of SX Virtual Link for any issues you may be having with firewall, Antivirus, or other issues.

With Windows Firewall, the software installation wizard can make an exception automatically.

With other 3rd party firewalls, the firewall is usually opened automatically the first time you use SX Virtual Link and you click YES to the prompt to open the connection, however sometimes manual exceptions need to be added.

To add the SX Virtual Link utility a firewall exception, make sure to add both the SX Virtual Link executable file, as well as the following network ports:

TCP IN 19540
TCP OUT 19540
UDP IN 19540
UDP OUT 19540


In general, VPN connections are also supported. Both IPSec and PPPTP connections are supported.

Since VPN routers always have the standard function to prevent broadcast packets to other networks, the USB device servers will not be found by SX-VL by itself. Please enter the IP of the device server directly under "Options" - "Search for device servers" after the broadcast packets have been activated. After that, the device server and the USB devices should be detected in SX-VL.

Port 19540 UDP and TCP in both directions must not be blocked by the router. Simple port forwarding or port forwarding in combination with NAT is not supported. Also the Fritz!remote access solutions are not supported. 

Ensure direct USB connection work properly before using SX Virtual Link

If you are having any difficulties, please make sure your USB device works when connected directly with a USB cable to your computer before trying to use SX Virtual Link. If the device doesn't work directly over USB, it won't work when directly connected.

SX Virtual Link allows one person to connect to a USB device at a time, and is designed to work the same way a direct USB connection works. When one user connects to a device with SX Virtual Link, it is as if the user is plugging it directly to their computer with a USB port. When the user disconnects, it is just like unplugging the USB connection. SX Virtual Link has some features you may want to read about which allow users to share USB devices easier.

Using Printers with SX Virtual Link

Silex USB Device Servers have a "Printer Autoconnect" feature allowing multiple users to share a printer, much like a print server, without the need to manually connect or disconnect. If you are having difficulties sharing a USB Printer with SX Virtual Link among multiple users on a network, you will want to make sure that the "Printer Autoconnect" feature is working properly. To configure this feature, please read the HELP documentation in SX Virtual Link by clicking on the '?' and click on 'How to Use a Printer' within the Help.

When the printer is not being used, it will show as 'Offline' on your computer (similar to having your USB cable disconnected). Don't worry, your printer is available, it's just not "connected". Once configured for Printer Autoconnect, when you Print, the SX Virtual Link Printer Autoconnect feature will automatically connect, then the job will print, then it will disconnect freeing the printer up for the next user.

If you are having difficulty with a printer, try making sure it prints when directly connected to your computer with the USB cable. Then make sure you have printer autoconnect set up correctly. You can do this by right-clicking on the printer in SX Virtual Link, going to 'Properties', then the 'Optional Settings' tab, then make sure there is a green checkmark and it says "Auto Printer Connect can be used". You can click on "Confirm" just to be certain and select the installed printer driver. If you are having difficulties with SX Virtual Link disconnecting before the printing is complete, it is because some printers try to hang on to the connection longer. You can increase the 'time before disconnecting after print job is sent'.

Using USB Scanners (including scanner function of MFPs) and USB Disk Drives with SX Virtual Link

USB Devices like scanners and Disk Drives or Flash Drives work the same way they do when directly connected to the computer. Remember, the speed may not be quite as fast as when you have a direct USB connection since the network speed is often not the same speed as a direct USB connection.

If you want multiple users to be able to connect to a USB disk drive, USB scanner, or other device besides a printer (one connection at a time as stated earlier), you will want to make sure the selection to "Automatically Connect this device when it is available" is not checked. If one of the computers is set up with this option on a device, it will make it difficult for others to connect.

Difficulties connecting to the USB Device or staying connected to a device with SX Virtual Link

SX Virtual Link depends on the network (or wireless network) connection to stay connected. If you don't have a good network connection to the SX Virtual Link enabled device, you may have difficulty using SX Virtual Link successfully.

If you are using SX Virtual Link with a wireless connection, and are having difficulties maintaining a strong connection to your network, try moving your computer, making sure the antennas have a solid connection if you are using a router, and making sure your computer is not near metal surfaces or other radio frequency devices.

Install SX-Virtual Link as a service

Please download the software available on the SX-Virtual Link software page to install SX-Virtual Link as a service.

Can I use SX-Virtual Link on VMWare ESX Server or Citrix Server or Microsoft Hyper-V?

Yes, it is compatible in general.

Please make sure that the drivers for USB are installed, our system depends on the Windows drivers, so if your virtual system does not have any USB hub hardware the drivers for USB might be not installed.

Since ESX Server or Hyper-V does not provide direct support for USB, USB drivers are not installed in the guest operating system by default. The software SX-Virtual Link depends on the USB core files to install properly. To enable the rest of the installation to proceed normally, copy and rename the required file from the original operating system CD.
• Source: usbd.sy_ in the I386 directory of the CD
• Destination: usbd.sys in the system32 drivers directory of the guest operating system
If this does not work you might need to extract the file from the "" and copy it to the given location.

After copying this file, reboot your machine. You can then continue with the normal SX-Virtual Link installation.
Please make sure that your guest OS has direct access to the network. NAT is not supported.
Hyper-V is not yet offically tested, the information about the support of Hyper-V is at the moment based on experience from Microsoft technical support. Please test on non-productive systems in advance.