Forum Discussion
Not able to set wallpaper on managed chromebook using the Policy API from GWS
Hello Team,
While testing the wallpaper management functionality using the Chrome Policy API, we observed that the wallpaper does not get applied on managed ChromeOS devices, even though the API calls return a successful response.
When we upload the wallpaper image using the uploadPolicyFile endpoint, it successfully returns a valid downloadUri.and wallpaper gets applied on device. However, when we attempt to apply this uploaded image as a wallpaper using the Policy API, the request completes successfully (200 OK), but the wallpaper does not apply on the chromebook device.
We’d appreciate your help confirming the following points:
Are there any additional parameters, permissions, or policy fields required for either of the following?
chrome.users.Wallpaper
chrome.devices.managedguest.Wallpaper
Are there any known propagation delays, caching behaviors, or policy refresh constraints that could affect wallpaper deployment on managed devices?
Hi VishalSanap08 welcome to the community and thanks for your question.
Can I check you are using the specific JSON structure required in the Policy API request, not just the URI?
The value you send for the policy must be a JSON object containing:
- url: The downloadUri from the uploadPolicyFile endpoint.
- hash: The SHA-1 hash of the uploaded image file. This is critical for integrity check.
- placement: Set to CENTER_CROP.
- source: Set to POLICY.
Example JSON Value (Policy API Payload): {"url": "...", "hash": "...", "placement": "CENTER_CROP", "source": "POLICY"}
Also I include some initial troubleshooting steps to consider:
- Verify JSON Structure: Double-check that your Policy API call includes the SHA-1 hash and all required fields (url, hash, placement, source) in the value payload.
- Force Refresh: On a test Chromebook, go to chrome://policy and click Reload policies. Check if the new wallpaper policy value (including the url and hash) appears correctly on this page. If it is correct, wait a few minutes for the device to download the file.
- Check Permissions: Ensure your service account/user has the correct Admin SDK Directory API permissions to manage User or Device policies, as applicable.
Let's also see if any other IT Admins across the community have advice on this topic.
2 Replies
Thanks Lynda. This was helpful. I was able to set wallpaper successfully
Hi VishalSanap08 welcome to the community and thanks for your question.
Can I check you are using the specific JSON structure required in the Policy API request, not just the URI?
The value you send for the policy must be a JSON object containing:
- url: The downloadUri from the uploadPolicyFile endpoint.
- hash: The SHA-1 hash of the uploaded image file. This is critical for integrity check.
- placement: Set to CENTER_CROP.
- source: Set to POLICY.
Example JSON Value (Policy API Payload): {"url": "...", "hash": "...", "placement": "CENTER_CROP", "source": "POLICY"}
Also I include some initial troubleshooting steps to consider:
- Verify JSON Structure: Double-check that your Policy API call includes the SHA-1 hash and all required fields (url, hash, placement, source) in the value payload.
- Force Refresh: On a test Chromebook, go to chrome://policy and click Reload policies. Check if the new wallpaper policy value (including the url and hash) appears correctly on this page. If it is correct, wait a few minutes for the device to download the file.
- Check Permissions: Ensure your service account/user has the correct Admin SDK Directory API permissions to manage User or Device policies, as applicable.
Let's also see if any other IT Admins across the community have advice on this topic.
