Error: "Couldn't Connect to the Server" After MCP Authorization Succeeds

Error: "Couldn't Connect to the Server" After MCP Authorization Succeeds

Info
If you finished signing in to connect the Power My Analytics MCP connector, saw "Authorization Successful!", and your AI client still shows a connection error right afterward, this article walks you through the fix. For full setup and troubleshooting, see the Power My Analytics MCP Server Guide and Troubleshooting and Important Considerations for PMA MCP Server.

Error

"Couldn't connect to the server. Check that the URL points to a valid MCP server."

Data source affected: The Power My Analytics MCP connector (Claude Desktop, Claude Web, ChatGPT, or another MCP-compatible client).

Occurs: Right after you finish signing in for a new or reconnected MCP connection. Your AI client's Connectors panel shows the Power My Analytics entry in a "Connection issue" state, usually with only a Reconnect option available.

Cause

Your sign-in with Power My Analytics finished and a token was issued, but the connection step that runs immediately afterward didn't complete. This is usually one of: the connection attempt timing out, your client needing a fresh registration with the PMA server, or a corporate network or proxy allowing the sign-in page through while blocking the ongoing connection that follows it.

Notes
Clicking Reconnect does not resolve this. Reconnect reuses the same registration that failed to complete; you need to remove the connector and add it again so it registers fresh.

Solution

  1. Remove the Power My Analytics connector completely (not just Reconnect):
    • Claude Web: go to Settings > Connectors (or claude.ai/customize/connectors), find Power My Analytics, and disconnect it.
    • Claude Desktop: remove Power My Analytics from your connector list, then restart Claude Desktop.
    • Other MCP clients: remove the Power My Analytics custom connector from that client's connector or integration settings.
  2. Add the connector again from scratch at https://pma-mcp.web.app.
  3. Complete PMA sign-in right away. Don't leave the authorization page open partway through: the pending sign-in session is valid for about 10 minutes, so finishing without a long pause matters.
  4. Confirm the connection registered on the PMA side. In your Hub, go to Organizations > MCP and check the Connected Application table. A new row for your client confirms the connection registered successfully. If you don't see one after a few tries, contact support using the details below.
Notes
These steps won't help in three specific cases: an inactive PMA subscription, a per-minute rate limit you've temporarily hit, or a manually created API token pasted in where the sign-in flow expects one. If one of those applies, restore billing, wait about a minute, or connect through the normal sign-in instead, rather than repeating remove-and-re-add.
Alert
If more than one person on the same network runs into this, a corporate proxy or firewall may be the cause. It can let the ordinary PMA sign-in page through while closing the longer-running connection your AI client opens right after. To test this, have one affected person repeat steps 1 through 3 on a different network (a phone hotspot works well). If it connects there, ask your IT team to allow https://pma-mcp.web.app and permit long-lived streaming responses through the network.

When to Contact Support

Submit a ticket if:

  • The Connected Application table doesn't show a new row after a few attempts.
  • These steps don't clear the error.

When you reach out, include which AI client you're using (Claude Desktop, Claude Web, ChatGPT, or other), whether you're on a shared office network, and a screenshot of the error if you have one.