What you will have at the endA useful next step based on the actual check error, rather than repeated retries.
Before you start
Open the monitor detail page and read the error under Monitor settings. A failed check keeps the last successful snapshot, so you can recover without replacing a good baseline with an error page.
Check the URL and response
Use a complete HTTP or HTTPS URL without embedded credentials. Local/private network addresses, custom ports, and direct PDF sources are not supported. If the website is down or returns an error, open it yourself and retry after it is available.
Use your browser for login or dynamic content
A server check does not share your browser’s login session and does not execute page JavaScript. When the page requires login or has no readable server-rendered text, switch to Use my browser, sign in on the website, and capture the fully loaded page with the helper.
Simplify the selector
An invalid selector or one that no longer matches will fail. Try clearing the CSS selector, save, and check again. Once the whole-page capture works, add a stable selector and verify the latest snapshot. In browser mode, the helper and monitor selectors must be identical.
Respect the cooldown
Wait at least one minute before checking the same monitor again. Guest workspaces allow three live checks per day. Other service limits can also require a pause. Repeated clicks cannot make a blocked or unavailable page respond sooner.
Ask for help with context
If it still fails, use Contact and include the public source URL, checking method, and error message. Do not send account passwords, session cookies, private page contents, or checker credentials.