"Connection failed" or "couldn't authenticate" with Webflow

You clicked Connect Webflow site on the Webflow connect page, the OAuth window opened (or didn’t), and something went wrong. Symptoms look like: Specter says it couldn’t reach Webflow, the OAuth window closes without completing, Webflow shows an error before you even see the approval screen, or the Mac app never receives the handoff. Almost always one of the six causes below.

1. Pop-up blocker stopped the OAuth window

OAuth opens a new window to Webflow so you can sign in and approve the install. If your browser blocked the pop-up, you may have seen nothing happen, or a tiny “blocked” indicator in the address bar.

Fix: allow pop-ups for spectersync.com (or for the page you started from), and try again. If you’re in a strict-privacy browser like Brave or Safari with content blockers cranked up, temporarily relax them for the connect flow.

2. Your Mac didn’t catch the deep-link back to Specter

Webflow’s approval flow ends by handing off back to the Specter Mac app via a deep link (specter://oauth/complete?provider=webflow&code=...). If Specter wasn’t running, or macOS didn’t route the link, you can land on a “you’re connected — return to Specter” page but the app never picks it up.

Fix: make sure Specter is running (you’ll see the menu-bar icon), then click Connect Webflow site again from the setup page. If macOS asks whether you want to allow the deep link, say yes.

3. You’re signed into the wrong Webflow Workspace

Webflow’s authorization screen is Workspace-scoped — you’re approving access to the sites in whichever Workspace the browser session is currently in. If you have multiple Workspaces (a personal one, a client one, an agency one), the wrong one may be active in your browser when you start the flow, so the sites you want to sync don’t appear on the approval screen.

Fix: in a separate tab, sign in to Webflow and switch to the correct Workspace. Then return to the setup page and start the connection again.

4. The OAuth scopes were declined or the site wasn’t picked

On Webflow’s authorization screen, you have to both approve the scopes (sites:read, cms:read, cms:write) and explicitly pick which sites Specter can access. If you decline a scope, or if you accept the scopes but don’t tick any sites, the handshake completes but Specter has nothing to read.

Fix: run the flow again. On the approval screen, leave all three scopes checked and tick the sites you want to sync. If you only want Specter to see one of your sites, tick only that one — Specter will only see what you authorize.

5. Your role on the Webflow Workspace can’t install apps

If you’re a guest or limited-role member on the Workspace, Webflow may not let you complete an app install. The approval screen will show a permissions error rather than the normal site picker.

Fix: ask a Workspace admin to either grant you the install permission, or to complete the connection from their own account. Once Specter is authorized for the site, anyone on the team can use the Specter Mac app to sync — the OAuth token lives in the keychain of whichever Mac ran the install, but each teammate can run the install on their own machine for sites that are already authorized at the Workspace level.

6. The Webflow plan doesn’t include the CMS

Specter syncs the Webflow CMS. The Basic site plan doesn’t include the CMS — it’s only on the CMS, Business, and Enterprise plans (or Workspace plans publishing to CMS-enabled sites). On a Basic site, there are no collections to sync, so even a successful OAuth handshake will leave Specter with an empty list.

Fix: confirm the site you want to sync has the CMS enabled. If it doesn’t, upgrade the site plan in Webflow, then re-run the connection from the setup page.

Still stuck

If you’ve ruled out all six, the next step is to revoke and reconnect cleanly:

1. In your Webflow dashboard, go to Workspace → Apps & integrations → Authorized apps, find Specter, and click Revoke. That immediately invalidates the access token on Webflow’s side.
2. In Specter on your Mac, remove the connection from the connected-sites list.
3. Run the flow again from the setup page.

If none of that helps, email support@spectersync.com with a screenshot of the error — that’s almost always faster than guessing.