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# ADP - How do I link my account?

# Overview

To authenticate with ADP, you need:

1. **Client ID** - A unique identifier for your client.
2. **Client Secret** - A confidential key used to authenticate the identity of the application (client).
3. **Client Public Certificate** - The public certificate (in PEM format) used for Mutual TLS (mTLS) authentication.
4. **Client Private Key** - The private key (in PEM format) associated with the client certificate, used for establishing a secure TLS connection.

This guide will walk you through obtaining these credentials within ADP.

### Prerequisites:

* You must have an account with ADP.

### Instructions:

#### Step 1: Finding Your Client Credentials

1. Log in to your ADP Developer account.
2. Navigate to the **Apps** section of the Developer Portal.
3. Click on the **Register App** button.
4. Fill in the required information for your app.
5. Agree to the ADP Developer Terms of Service and Privacy Policy.
6. Click the **Submit** button to complete the app registration process.
7. Once you are done with the registration process, you can obtain your credentials by navigating to the **Apps** section of the Developer Portal.
8. Click on the name of the app you just registered above.
9. Click on the **Credentials** tab to view your app's **Client ID** and **Client Secret**.

#### Step 2: Generating the Private Key and Certificate Signing Request

* To authenticate with ADP APIs using Mutual TLS (mTLS), you'll need to generate a **private key** and a **Certificate Signing Request (CSR)**. This allows ADP to issue a signed certificate used for secure communication.

Follow the steps below to complete this process:

1. Install OpenSSL

* **Windows**: Download and install OpenSSL Light from [http://slproweb.com/products/Win32OpenSSL.html](http://slproweb.com/products/Win32OpenSSL.html)
* **Mac**: OpenSSL is already included on macOS. You can skip to step 3 and use **Terminal**.

2. Open a Command Prompt and Navigate to OpenSSL

Open `cmd.exe` and navigate to the OpenSSL binary directory:

```bash theme={null}
# For 32-bit version
cd "C:\Program Files (x86)\OpenSSL-Win32\bin"

# For 64-bit version
cd "C:\Program Files\OpenSSL-Win64\bin"
```

3. Generate the Private Key

Run the following command to generate a 2048-bit RSA private key:

```bash theme={null}
openssl genrsa -out companyname_auth.key 2048
```

This creates a file named `companyname_auth.key`, your private key. Keep it safe and **do not share** this file.

4. Generate the Certificate Signing Request (CSR)

Using the private key, generate the CSR by running the following command:

```bash theme={null}
openssl req -new -key companyname_auth.key -out companyname_auth.csr
```

When prompted:

* Leave the **Country**, **State**, **Locality**, and **Challenge Password** fields **blank**
* Use the correct **Organization Name** that matches your ADP registration
* Set the **Common Name** as your company name followed by `MutualSSL` (e.g., `ExampleCorpMutualSSL`)
* **Avoid using special characters** in any of the fields

This generates `companyname_auth.csr`, which you'll submit to ADP.

5. Next you will need to submit the CSR to ADP. Open the **[ADP Certificate Signing Tool](https://cert-manager.com/customer/adp/device/adpwebservices/login)** (no login required)
6. Select **"Authentication and Transaction Signing"** for the certificate type
7. Paste the full contents of your `.csr` file, including the header and footer:

```
-----BEGIN CERTIFICATE REQUEST-----
...
-----END CERTIFICATE REQUEST-----
```

8. Provide your:
   * Technical contact's **email address**, **name**, and a **group email** (for renewal notifications)
   * **Company name**
   * **ADP client ID**\
     *(If you're using ADP Workforce Now, your client ID is the portion after the `@` in your ADP login.)*

9. Receive and Save the Signed Certificate

Once approved, ADP will return a signed certificate. Save it as:

```
companyname_auth.pem
```

Place this file in the same directory where you created the `.key` and `.csr`.

***

✅ Files You'll Use for Mutual TLS Authentication

For API authentication with ADP, you'll need the following two files:

* `**companyname_auth.key**` — the **Client Private Key**
* `**companyname_auth.pem**` — the **Client Public Certificate**

Make sure both files are stored securely and access is restricted to authorized systems and personnel.

#### Step 3: Enter credentials in the Connect UI

Once you have your **Client ID**, **Client Secret**, **Client Public Certificate** and **Client Private Key**:

1. Open the form where you need to authenticate with ADP.
2. Enter your credentials in their respective fields.
3. Submit the form, and you should be successfully authenticated.

<img src="https://mintcdn.com/nango/pqeep5ccKTsyW8Sp/integrations/all/adp/form.png?fit=max&auto=format&n=pqeep5ccKTsyW8Sp&q=85&s=fa4979126d93532ab065d62425336bf1" style={{maxWidth: "450px" }} width="1000" height="1388" data-path="integrations/all/adp/form.png" />

You are now connected to ADP.