Title: Problems with conecting Subdomain
Last modified: August 11, 2026

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# Problems with conecting Subdomain

 *  [superyeti](https://wordpress.org/support/users/superyeti/)
 * (@superyeti)
 * [4 days, 3 hours ago](https://wordpress.org/support/topic/problems-with-conecting-subdomain/)
 * Hi I tried to connect two wp installation that are located on a subdomain. not
   especialy staging.
   With my other wp installations which are top lvl domains I
   did not have any problems. Claude opens the verification page in my browser and
   I hit allow. after that I get the error that it has failed. the plugins activity
   log shows nothing. I also tried with oauth client instead of regular mcp url.
   Is this a known problem? and is there a workaround? havent found something in
   the docs.Thank you in advance

Viewing 1 replies (of 1 total)

 *  Plugin Support [rpteam](https://wordpress.org/support/users/rpteam/)
 * (@rpteam)
 * [4 days, 3 hours ago](https://wordpress.org/support/topic/problems-with-conecting-subdomain/#post-18989974)
 * Hi [@superyeti](https://wordpress.org/support/users/superyeti/),
 * Happy to dig in. A few pieces of info I’ll need to diagnose this:
    1. The exact subdomain URL you’re connecting to — the full MCP Server URL as shown
       in Royal MCP →Settings → General (e.g. [https://mcp.example.com/wp-json/royal-mcp/v1/mcp](https://mcp.example.com/wp-json/royal-mcp/v1/mcp)).
    2. Which client — Claude.ai web (custom connector), Claude Desktop, or ChatGPT?
    3. The exact error text shown by the client after you click Authorize. A screenshot
       is fine.
    4. How the subdomain is set up — is it a separate WordPress install with its own
       database, a WordPress Multisite subsite, a reverse proxy pointing to a directory
       install, or something else? And is it on the same host / behind the same Cloudflare(
       if any) as your working top-level domain?
    5. Was this working at any point before now or no?
 * Meanwhile, three quick self-checks that resolve most subdomain OAuth issues:
 * a. Confirm discovery is reachable at the subdomain. In your browser (not the 
   plugin), open:
 * [https://YOUR-SUBDOMAIN.example.com/.well-known/oauth-authorization-server](https://YOUR-SUBDOMAIN.example.com/.well-known/oauth-authorization-server)
 * You should see a JSON response with issuer, authorization_endpoint, token_endpoint,
   registration_endpoint fields — and every one of those URLs should point to the
   subdomain, not to your
   top-level domain. If any point to the wrong host, that’s
   the root cause.
 * b. Check WordPress Address + Site Address. WP Admin → Settings → General on the
   subdomain install — both fields must be the subdomain URL, not the top-level.
   A mismatch here makes Royal MCP advertise the wrong discovery endpoints.
 * c. Save Permalinks. WP Admin → Settings → Permalinks → Save Changes (no changes
   needed — the save
   action flushes WordPress rewrite rules, which serve the .well-
   known/oauth-* paths). This resolves caseswhere OAuth endpoints 404 despite the
   plugin being active.
 * “Activity Log shows nothing” is a strong diagnostic signal — it usually means
   the request never reached
   PHP at all, which points at either broken rewrites (
   see step c) or the client hitting the wronghostname (see step a). Once you share
   the subdomain URL + client + error, we can narrow it fast.
 * RP Team

Viewing 1 replies (of 1 total)

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 * 1 reply
 * 2 participants
 * Last reply from: [rpteam](https://wordpress.org/support/users/rpteam/)
 * Last activity: [4 days, 3 hours ago](https://wordpress.org/support/topic/problems-with-conecting-subdomain/#post-18989974)
 * Status: not resolved