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Troubleshooting Viscosity Problems (Windows)

In rare instances Viscosity, or one of its components, may encounter a problem that prevents it from being able to function correctly under Windows. Below you can find some solutions to the more common issues you might face. Most issues relating to the driver, network adapter or service on Windows are generally caused by Antivirus or Network Security software. We recommend to disable any such software when following this guide.

If the problem you are encountering is not listed here, please check the Troubleshooting Connection Problems article for common connection problems and solutions for them.

Background Service Not Running

If you continue to see this message when trying to connect and you have been able to successfully connect in the past, first simply try to restart your PC to release any blocks or locks on your computer. Before you do this though, if you run any Antivirus or Network Security software, add an exception for the following files:

  • C:\Program Files\Viscosity\Viscosity.exe
  • C:\Program Files\Viscosity\ViscosityService.exe

If after a reboot you continue to see this message, you may need to reinstall the service. To do so:

  1. Disable any Antivirus or Network Security Software
  2. Download the latest version of the Viscosity Installer here
  3. Run the installer and follow the installation instructions
  4. Start Viscosity and attempt to connect again

If after following these instructions you continue to see this problem, the most likely cause is another application is either blocking the service, the service connection, or has quarantined the service. The easiest way to resolve this is an uninstall/reinstall. Please try the following:

  1. Add an exception to any Antivirus or Network Security software you run for Viscosity following the instructions above if you have not already
  2. Uninstall Viscosity by following these instructions. You do not need to remove your connections and settings.
  3. Restart your PC (it is important this is actually done to release any locks in Windows)
  4. Download the latest version of the Viscosity Installer here
  5. Run the installer and follow the installation instructions
  6. Start Viscosity and attempt to connect again

Slow Connection or Requests Timing Out Over VPN

Recent version of Viscosity (1.5.6 and later) include a new network driver for Windows 7+. This driver allows for greater performance and compatibility. However, in some rare circumstances under Windows 7 and 8/8.1 it may clash with an older setup or software. If you are connected correctly (please check your OpenVPN Log for any errors), then rolling back to the legacy driver may help alleviate this. To do this:

  1. Download the latest version of the Viscosity Installer here
  2. Run the installer
  3. At the Components page, select Legacy Driver in the list
  4. Continue with the installation
  5. Attempt to connect again

If the problems persist after this, we recommend contacting your VPN Provider.

Adapter Creation Failed or Adapters appearing as Unknown Devices

This error generally occurs when the Viscosity driver has not been installed correctly or has become damaged or corrupt by another application. To remedy this, reinstall Viscosity ensuring to click Install at the driver prompt. Pressing Enter will cancel the installation of the driver, so please ensure that you click Install.

To reinstall Viscosity:

  1. Download the latest version of the Viscosity Installer here
  2. Run the installer
  3. Continue with the installation
  4. Attempt to connect again

Large Number of Adapters Present

If you have a lot of connections, or import a lot of connections, you may find a large number of Viscosity adapters being created. While this will generally have no impact on the performance of your PC, some users prefer for this not to happen. The simplest fix is to use Single Adapter Mode (Windows).

The easiest way to remove the unwanted adapters is to simply Uninstall Viscosity, ensuring that you don't remove your connections and settings, and then Install Viscosity again.

CreateFile failed on TAP device

If you see this message appear in the log on Windows 7, you may be behind on Windows Updates. The issue is caused due to missing a Windows update which allows SHA2 signing certificates to be used. You may see the following error when viewing the device status in Device Manager:

Windows cannot verify the digital signature for the drivers required for this device. A recent hardware or software change might have installed a file that is signed incorrectly or damaged, or that might be malicious software from an unknown source. (Code 52)

The specific update required is here for 64 bit systems, or here for 32 bit systems. Download and install this update (KB3033929) and then restart your computer and attempt to connect again. If you are unsure if you are using 32 or 64 bit, please follow the instructions here.

We recommend you keep Windows Updated, either by setting Windows to update automatically, or running Check for Updates regularly.

If you are on an operating system other than Windows 7, or the above update has not resolved this message, please see the Adapters appearing as Unknown Devices section above.

Viscosity Does Not Start

If you start Viscosity and the system tray icon does not appear, or Viscosity closes immediately, this is generally caused by Antivirus software falsely blocking Viscosity. To relieve this issue, most Antivirus software allows you to add an exception for software. We recommend you add an exception for Viscosity.exe, ViscosityService.exe and openvpn.exe, these are generally located at C:\Program Files\Viscosity unless you installed Viscosity in a different location.

We also recommend you request your Antivirus provider to white list Viscosity, most Antivirus software providers have a section on their website to do this.