Fix rejected or failing webhook notifications

Resolve invalid hosts, missing test messages, disabled page channels, and incident delivery failures.

Last checked 21 August 2026

Work through the symptom that matches what you see. Slack, Microsoft Teams, and Discord use the same overall flow, but TechDash validates each platform's host separately.

TechDash rejects the URL

TechDash accepts only complete HTTPS URLs on recognized hosts:

  • Slack: exactly hooks.slack.com
  • Discord: discord.com, discordapp.com, or a subdomain ending in .discord.com
  • Microsoft Teams: webhook.office.com or its subdomains, plus subdomains of logic.azure.com or api.powerplatform.com

Copy the complete incoming webhook or external workflow URL from the platform. Do not paste a workspace page, channel page, Discord invite, Teams browser link, shortened URL, or HTTP address.

The current error text is “That webhook URL is not a recognised Slack, Microsoft Teams, or Discord endpoint.” It can also appear when the URL belongs to the wrong field, such as putting a Discord URL in Slack webhook.

TechDash reports a network or timeout failure

TechDash sends one request with a fixed timeout and does not immediately retry.

Check:

  1. This computer has working internet access.
  2. A firewall, proxy, DNS filter, or security product is not blocking the platform host.
  3. The webhook or workflow still exists.
  4. The destination platform has not disabled it.
  5. The secret URL was not rotated.

Recreate the webhook or workflow and paste the new value when in doubt. TechDash saves fields as they change, so there is no separate Save button.

TechDash says the test was sent, but no message appears

TechDash treats a completed request as success without checking whether the remote service accepted it. A platform can reject the message and the UI may still show “Test notification sent.”

Confirm the message appears in the destination. If it does not:

  • Verify the webhook points to the intended workspace, team, server, and channel.
  • Recreate the webhook instead of editing its secret URL.
  • For Teams, use the standard Send webhook alerts to a channel workflow. A flow restricted to people in your organisation requires Microsoft authentication and will not work as a normal external webhook.
  • Check whether the platform changed or disabled the workflow.
  • Send a fresh test after replacing the URL.

TechDash does not currently show the remote service's response details.

The test arrives, but incidents do not

Tests bypass incident rules. Check:

  • Slack, Microsoft Teams, or Discord is On under Notify for the relevant monitored page.
  • A global webhook URL remains in the corresponding field.
  • A built-in incident is Warning or Critical. Built-in Advisory incidents do not notify.
  • A Custom Check has Notify enabled. Its severity alone does not decide delivery.
  • The check is not listed in Notifications > Ignored Checks.
  • The event is a new failure or severity escalation, not an unchanged open issue.
  • Notify when a check recovers is On if you expected a Good recovery message.
  • TechDash was running and monitoring was active when the new result completed.

For a sitewide issue, check the / monitored page's channel toggles. If there is no monitored root page, TechDash uses the first monitored page for that website.

Incident attempts can fail silently in the UI

Incident webhook sends run in the background. A network error or timeout can fail without showing on the Notifications page, and TechDash does not retry it in a tight loop. A later qualifying incident or recovery is a new send attempt.

This means the absence of a message does not always imply that page policy blocked it. Use Send test to check the route, then confirm the message appears at the destination.

Replace or remove a stored URL

TechDash encrypts webhook URLs before saving them in local settings. Editing a field changes future sends only. Clearing it disables that global webhook channel without changing page toggles or past alert records.

Treat every webhook URL as a password. If it was exposed, revoke or rotate it on the platform first, then replace it in TechDash.

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