topic Re: OAuth: "An error occurred validating the app authorization." in APIs & Integrations

OAuth: "An error occurred validating the app authorization."

EricPopelka — Thu, 21 Aug 2025 17:26:59 GMT

Hello,

Our HubSpot app stopped working unexpectedly today.

When we go to the OAuth screen in HubSpot, we get an error that says "An error occurred validating the app authorization." We've noticed that this error seems to happen for any app that we attempt to authorize using our hubspot@lyntonweb.com account. In other words, using that account means that we can't install any apps anymore - we just get a spinning wheel and then the error screen.

If we don't get that error, then instead what happens is that the customer's HUB ID doesn't show up in the list of portals to connect to at all. We know we have access to those portals because we can sign into them with the account, but if we try to connect our app, we can't see the portal in the list of portals that the account has access to.

Re: OAuth: "An error occurred validating the app authorization."

STierney — Fri, 22 Aug 2025 00:10:31 GMT

Hey @EricPopelka - thanks for posting in the Community!

I'd like to tag in some experts here to see if they have any insight as to what may be causing this issue for you and your team!

@Teun, @ChrisoKlepke, and @louischausse - any thoughts on how @EricPopelka may be able to mitigate this error?

Shane, Community Manager

Re: OAuth: "An error occurred validating the app authorization."

RubenBurdin — Fri, 22 Aug 2025 20:47:44 GMT

Hi @EricPopelka

That error usually pops up when the OAuth flow can’t properly validate your account or portal access. A couple of things worth checking:

Make sure the app’s redirect URL in your developer settings exactly matches what HubSpot expects (even a trailing slash mismatch will break it) – HubSpot has a note on this in their OAuth guide here:

(https://developers.hubspot.com/docs/guides/apps/authentication/oauth-quickstart-guide )

Confirm that the hubspot@lyntonweb.com account is actually a Super Admin in the target portals. If it’s not, the list of portals won’t show during app install

(https://knowledge.hubspot.com/user-management/hubspot-user-permissions-guide )

Sometimes cached sessions in the browser can interfere log out of all HubSpot accounts, clear cookies, and retry the OAuth floww

If nothing works, try generating a new client secret in your app settings and re-run the authorization.

I’ve also seen teams run into this when tokens aren’t rotating properly.

If you’re juggling multiple systems, a workflow automation platform like Stacksync can handle OAuth token management in the background and keep integrations stable so errors like this don’t block you mid-day.

Hope this helps.

Re: OAuth: "An error occurred validating the app authorization."

EricPopelka — Tue, 26 Aug 2025 18:56:29 GMT

Thanks for checking on this thread, Shane! The issue is ongoing sadly. We have determined that it is isolated to a single user account. Since we are a HubSpot agency, we have an account that our support engineers use to assist when customers have questions. The general business flow is this:

Customer writes in; e.g., "This record did not sync." -> Customer opens tickets with us -> We sign into their HubSpot and troubleshoot workflows, etc.

It appears that trying to authorize ANY HubSpot app results in the error message regarding an error validating the app authorization. See this loom: https://www.loom.com/share/bb160ccb7e014375989f355bc98cce13?sid=7e54d822-6902-49a9-aaef-8eadf411a567

I've got a ticket open with HubSpot support. Any additional assistance is very very much appreciated as our support engineers are dead in the water if they can't sign into TIBCO Scribe Online or Tray.io's HubSpot apps using our agency account.

Re: OAuth: "An error occurred validating the app authorization."

STierney — Tue, 26 Aug 2025 20:05:47 GMT

Hey @EricPopelka - thank you for providing this update!

As this extends beyond my personal knowledge base, I'm wondering if @RubenBurdin has any follow up thoughts here. The good news is that you at least have Support working on the issue while we try to get some other experts tagged into the conversation!

Please keep us posted!

Shane, Community Manager

Re: OAuth: "An error occurred validating the app authorization."

EricPopelka — Tue, 26 Aug 2025 20:18:21 GMT

Hi Shane!

Yes, so I would love to get your input here. Support has stated that my customer did not give the agency account the support permissions in HubSpot. However, if you watch this Loom, you can see that the problem occurs before a specific customer is selected. So any efforts you can make to help me and support get on the same page about that are much appreciated.

Ultimately, we understand that the shared email may not be ideal from a compilance POV. We are fully committed to working with HubSpot on whatever a replacement for it is, but we need to be told what it is. Right now, this is taking the form of a random outage/timeout thing and not a violation of policy. We look forward to aligning with you on this. Thank you so much, Shane!

Re: OAuth: "An error occurred validating the app authorization."

STierney — Tue, 26 Aug 2025 20:38:48 GMT

Hey @EricPopelka - appreciate this context!

While the developer side of things is still outside of my purview, I was able to find this Community thread, which addresses the same issue as well as the fix. Would you mind taking a look and providing any context regarding whether or not this helps?

Shane, Community Manager

Re: OAuth: "An error occurred validating the app authorization."

EricPopelka — Tue, 26 Aug 2025 20:44:59 GMT

Hi Shane - Sadly that link doesn't help with the problem I'm facing. None of our apps, or apps from other vendors, work. So the problem is not isolated to apps that ask for the "reports" scope. However I do think this problem is isolated to the agency email, so I'm glad that I've got HubSpot support on the case. Thank you for keeping on top of these threads, I really appreciate it.