KB-1118 Connector lines in the Process Model do not render in Internet Explorer

Symptoms

When using the Process Modeler in Internet Explorer, users experience the following behavior:

• Users are unable to create new connector lines between nodes.
• Existing connector lines do not display.
• If any existing connector had Activity Chaining enabled, the Activity Chaining icon is rendered in the top-left portion of the Process Modeler window, separated from the nodes of the process model.

The following screenshot shows the behavior:

Cause

In order for the Process Modeler to render correctly, Appian utilizes a DLL file named vgx.dll, used explicitly for vector graphics rendering.

In response to CVE-2014-1776, many system administrators unregister this DLL from end users' machines. This results in rendering issues of the Process Modeler in Internet Explorer.

Action

The threat has been mitigated since its discovery, so users should feel comfortable enabling that DLL across their machines by performing the following steps:

1. Update Internet Explorer to the most recent version to ensure the fix for the threat is present.
2. Run a command prompt as administrator and execute the following commands:
   
   

   regsvr32 "%CommonProgramFiles%\Microsoft Shared\VGX\vgx.dll"
   regsvr32 "%CommonProgramFiles(x86)%\Microsoft Shared\VGX\vgx.dll"
   

Affected Versions

This article applies to Appian 16.1 and earlier using Internet Explorer as a web browser.