Hi everyone, I am running into a persistent 403 Permission Denied error when trying to use the `gemini-3-pro-image-preview` model via AI Studio and the API. The Issue: * Standard text models work fine with my key. * Standard “Flash” image models work fine (tested by toggling “Dev Mode” in my app). * Only `gemini-3-pro-image-preview` fails validation with “Permission Denied”. My Setup & Troubleshooting (Already Done): 1. Billing: My Google Cloud Project is definitely linked to an active Billing Account (Tier 1/Paid). 2. APIs: I have enabled both the Gemini API and Vertex AI API in the Cloud Console. 3. Permissions: I am the Project Owner and Billing Admin. 4. API Key: I created a brand new API key after linking billing. I even tried setting it to “Unrestricted” to rule out scope issues. 5. Model Terms: I went to Vertex AI Model Garden and accepted the terms for the preview model. Despite all this, I still get Permission Denied. Is there a specific allowlist for this preview model, or a known issue with new projects accessing it? Project ID: gen-lang-client-0470353870 Any help would be appreciated as I’ve spent hours debugging this loop.
The exact same problem that I’ve been working on 
Hi @Hank_Weiss , Welcome to the AI Forum!!!
Thanks for reaching out to us. 403 Permission Denied error often points to API key authentication and proper permissions for tuned models. If the issue persists, please connect with Google Cloud Support.
were you able to fix the issue ? ive been working all day with gemini-3 and suddenly it throws this 403 error…
There doesn’t seem to be a way to solve this issue. My API key works for Gemini 2.5 but not for 3. Even in the playground, I get “Internal Server Error”. Must be a problem on Google’s end.
Same here, google didn’t confirm yet a general problem but seems like that.
No I really don’t have a clue how to proceed. I created a new simple app just to test functionality and it works. But where the more complex app goes off the rails is difficult to tell.
Hank Weiss PhD, MPH, MS
Having the exam same problem, suddenly started a few hours ago. Went through the same steps you listed, and everything works fine with earlier Gemini models… Google side issues? Very odd.
I’m getting the same issue. gemini-2.5-pro works but gemini-3-pro returns 403 permission denied
Same here. Fine with 2.5 pro but still throwing 403 error with 3.0 pro. Paid api.
I am also getting 403 for Gemini 3 pro calls both through the rest API and google ai studio. Tried creating a new key but same problem persists.
I’m also hitting the issue, just on 3.0 Pro only . Flash and flash lite working fine for some reason.
Same here. 3.0 Pro only. Doesn’t work on playground either. I thought there’s a permission setting somewhere, but it seems to be happening to many users.
Same here. 3.0 Pro only, Google internal problem?
same I’ve been having this issue as well. Haven’t found a fix yet.
this thread is comforting that it’s not just me.
also had 3 working last night with no issues, today getting a 403 error. 2.5 pro and 2.5 flash working fine
I’m experiencing the same thing, no changes in permissions or API. Was working perfectly fine yesterday. I assume it’s an internal issue
I’m also getting the same issue. 2.5 os working but gemini-3-pro-preview is giving 403.
i have same problem as you guys
Same here… Have active billing setup, and have not reached the limits on the Google AI Studio dashboard. Very frustrating.