Message: Windows Fault Tolerant Heap (FTH) has been enabled for this application.

Reference Number: KB-03114
Last Modified: July 16, 2021

The information in this article applies to:

Chief Architect Premier or Chief Architect InteriorsHome Designer Professional or Home Designer Architectural or Home Designer Suite


I'm receiving the following message when I start my program:

"Windows Fault Tolerant Heap (FTH) has been enabled for this application. This may degrade performance."

What does this mean? 


The Fault Tolerant Heap is a subsystem of the Windows operating system that monitors application crashes and applies mitigations to prevent future crashes. This can, however, impact the performance of certain applications. When you're in this state, it's important to address the initial cause of the crashing. At your convenience, please follow the steps in the linked resource to troubleshoot crashing or closing in your Chief Architect program:  

Once Chief Architect is no longer crashing, Fault Tolerant Heap should no longer present itself. If you believe you have resolved the cause of the crashing, yet you're still receiving this error when you open your Chief Architect program, you can reset the Fault Tolerant Heap list manually. To do this, run the following command from an elevated (Administrator) command prompt:

Rundll32.exe fthsvc.dll,FthSysprepSpecialize

Note: To open an elevated (Administrator) command prompt, select the Windows start button and search: cmd. In the Search results, locate the Command Prompt application, right-click on it, and select Run as administrator. Click Yes to open an elevated (Administrator) command prompt window.

Right-click on Command Prompt, and choose Run as administrator

Running this command will clear all FTH applications, so applications that are currently functioning properly may begin to crash again after running this command.

To learn more about Fault Tolerant Heap and how to manage it on your system, please see the following Microsoft resource:

Note: The information mentioned in the resource above applies to the Windows 7, Windows 8/8.1, and Windows 10 operating systems.