Authentication Issue - Remote Access AEM Assets instance from AEM Sites

Hi ​@NageshRaja 

Can you confirm if you have the access for the remote DAM instance and are you using the SSO over there as well ?

Also, Can you please check the console and network tab and see if there is any error over there?

Hey ​@NageshRaja 

The authentication popup disappears but the Asset Selector gets stuck at "Waiting for user to authenticate..." because the IMS  configuration is incomplete or the CORS/authentication handshake between Sites and Assets instances is failing.

Solution

You need to configure the following:

1. IMS Configuration on Sites Instance

Ensure you have the Adobe IMS Configuration set up properly:

• Navigate to: Tools > Security > Adobe IMS Configurations

• Create/verify IMS configuration with:

  • Cloud Solution: Assets Essentials or Assets (depending on your setup)

  • Client ID and Client Secret from Adobe Developer Console

  • Authorization Server: 

    https://ims-na1.adobelogin.com

     (or appropriate region)

  • API Key (from Adobe Developer Console)

2. CORS Configuration on Remote Assets Instance

On the remote DAM instance, configure CORS to allow requests from Sites instance:

Create OSGi configuration: 

com.adobe.granite.cors.impl.CORSPolicyImpl-assets.cfg.json

{
  "alloworigin": ["https://your-sites-instance.aem.cloud", "https://your-sites-author.com"],
  "alloworiginregexp": [],
  "allowedpaths": ["/content/dam/.*", "/api/assets/.*"],
  "supportedheaders": ["*"],
  "supportedmethods": ["GET", "HEAD", "POST", "OPTIONS"],
  "maxage": 1800,
  "supportscredentials": true,
  "exposedheaders": []
}

3. Verify NextGenDynamicMediaConfigImpl Configuration

Ensure your OSGi config includes:

{
  "enabled": true,
  "imsOrg": "YOUR_IMS_ORG_ID@AdobeOrg",
  "repositoryId": "delivery-pXXXXX-eYYYYY.adobeaemcloud.com",
  "apiKey": "YOUR_API_KEY",
  "env": "dev"
}

4. Token Exchange Configuration

Create OSGi configuration: 

com.adobe.granite.auth.ims.impl.ImsConfigProviderImpl.cfg.json

{
  "ims.owning.entity": "YOUR_IMS_ORG_ID@AdobeOrg",
  "ims.technical.account.id": "YOUR_TECHNICAL_ACCOUNT_ID@techacct.adobe.com"
}

5. Clear Browser Cache & Cookies

After configurations:

• Clear browser cache completely

• Clear all Adobe-related cookies

• Restart AEM instances

• Try in incognito/private browsing mode first

6. Verify Network/Console Logs

Check browser console for:

• CORS errors

• 401/403 authentication errors

• Failed IMS token exchange requests

Look for errors related to:

•  

  ims-na1.adobelogin.com

   (or your IMS region)

• Token validation failures

7. Service User Mapping (if applicable)

Ensure service user has proper permissions on both instances:

com.adobe.cq.dam.remoteassets.impl.RemoteAssetsServiceImpl:remote-assets-service=remote-assets-service

Quick Checklist

•  IMS Configuration exists on Sites instance
•  CORS configured on Assets instance allowing Sites origin
•  API Key and IMS Org ID match in all configurations
•  Both instances are accessible via HTTPS
•  User has proper permissions on both instances
•  Browser cache cleared

The most common cause is missing or incorrect CORS configuration on the remote Assets instance. Start there first.

​@NageshRaja Quick follow-up! Were you able to get this issue sorted out? If you did, please consider posting the solution you used so others can learn from it. And if any of the replies above were helpful—whether they fully solved your problem or just pointed you toward the right fix—marking one as accepted helps future community members find solutions more easily. Closing the loop here makes a real difference for everyone.