Quick summary

On Windows 10, creating a site with a specific WordPress version (e.g. 6.8, 6.9) fails with “Cannot set up WordPress while offline”, even when the machine has a working internet connection. Creating a site with latest works.

Root cause: Studio’s isOnline() check (tools/common/lib/network-utils.ts) uses dns.resolve(), which fails on Windows when the bundled Node.js v24 reports DNS servers as 127.0.0.1 (known Node.js/c-ares regression: nodejs/node#62748). The OS resolver and system Node.js on the same machine work correctly.

This is not the same root cause as #3153 (SSL/cURL certificate issue), which shows the same user-facing error message.

Steps to reproduce

1. Install WordPress Studio 1.10.0 on Windows 10 (build 19045).
2. Confirm internet works (browser, etc.).
3. Open Studio → Add site → choose a WordPress version other than latest (e.g. 6.8 or 6.9).
4. Complete the form and create the site.
5. (Optional diagnostic) Run with Studio’s bundled Node:

$node = "$env:LOCALAPPDATA\studio_app\app-1.10.0\resources\bin\node.exe"
& $node -e "console.log('getServers:', require('dns').getServers()); require('dns/promises').resolve('public-api.wordpress.com').catch(e=>console.log(e.code, e.message))"

6. (Optional) Compare with system Node:

node -e "console.log('getServers:', require('dns').getServers()); require('dns/promises').resolve('public-api.wordpress.com').then(console.log)"

What you expected to happen

The site should be created with the selected WordPress version when the machine has internet access.

What actually happened

Site creation fails with:

Cannot set up WordPress while offline. Specific WordPress versions require an internet connection. Try using "latest" version or ensure internet connectivity.

Studio log excerpt:

[CLI - …] Checking WordPress version…
[CLI - …] Validating site configuration…
[CLI - …] Creating site directory…
Error occurred in handler for 'createSite': CliCommandError: [Last error message] Cannot set up WordPress while offline. …

On affected systems, bundled Node reports getServers: [ '127.0.0.1' ] and dns.resolve() returns ECONNREFUSED, while system DNS and Resolve-DnsName public-api.wordpress.com succeed.

Affected code path: desktop app forks bundled node.exe + resources/cli/main.mjs (apps/studio/src/modules/cli/lib/execute-command.ts), then isOnline() in tools/common/lib/network-utils.ts gates non-latest installs in apps/cli/commands/site/create.ts.

Impact

Some (< 50%)

Available workarounds?

No but the app is still usable

Platform

Windows

Logs or notes

Environment

• OS: Windows 10 (build 19045)
• Studio: 1.10.0 (commit 206258631711953a003bba8b933c0cf75e95baf7 from app logs)
• Locale: pt-BR
• System DNS: 192.168.0.1 (router)
• Bundled Node: v24.14.1 (c-ares 1.34.6) — dns.getServers() → ['127.0.0.1']
• System Node: v22.5.1 — resolves DNS correctly

Reproduction confirmed

• Without workaround: WP 6.8 and 6.9 fail in Studio UI (2026-06-06 and 2026-06-10).
• With latest: succeeds.
• latest uses bundled files under ~/.studio/server-files/wordpress-versions/latest and does not depend on isOnline().

Suggested fix (for maintainers)
Replace dns.resolve() with dns.lookup() in tools/common/lib/network-utils.ts, since lookup() uses the OS resolver and is unaffected by the c-ares regression.

Related

• Upstream: dns.getServers() returns 127.0.0.1 instead of actual DNS server on Windows (c-ares 1.34.6 regression) nodejs/node#62748
• Studio (different cause, same error text): CLI Error: cURL error 77 — Missing CA certificates in Studio container #3153
• Studio offline UI behavior: #1383 (forces latest when navigator.onLine === false; does not cover this CLI false positive)

I am planning to submit a PR with a fix in network-utils.ts in the coming days.