# Install the .NET Framework Agent (legacy)

### Important

If your applications are running on modern technology you should use the .NET Framework agent instead of the legacy agent.

The legacy .NET Framework agent offers the full capabilities of Contrast Assess, Protect, and OSS as of April 2020 but is no longer receiving new features or lower severity bug fixes. Contrast will continue to fix critical bugs in the legacy agent until January 10th, 2023.

You must have Editor role permission to install an agent.

The legacy Contrast .NET Framework agent can be used to analyze ASP.NET web applications running on legacy technologies including:

• Windows Server 2008

• Windows machines that cannot upgrade to .NET Framework version 4.7.1 or newer

• Applications that target the CLR2 runtime and cannot be upgraded to CLR4

See the legacy .NET Framework agent supported technologies and system requirements for more details.

To install the legacy .NET Framework agent:

1. Download the legacy .NET Framework agent (for example ContrastSetup_20.4.X.zip) where 20.4.X is the newest legacy version available.

2. Find the agent keys and create a YAML configuration file called contrast_security.yaml. Copy and paste this sample and replace the <Values> below with your values:

api:
url: <YourContrastURL>
api_key: <YourAPIkey>
service_key: <YourServiceKey>

6. Run ContrastSetup.exe. This installs the .NET agent.