Webhooks "Unacceptable URL" Error - FogBugz On-Premises



Launching webhooks fails with "Unacceptable URL" no matter how simple the webhook configuration is.

FogBugz On-Premises has a built-in local traffic detection mechanism to prevent webhooks from hitting sites in the internal network. The intent behind this is to prevent external users from making FogBugz a jumping-off point to explore the local network.

Usually, this feature is not viewed as a limitation because users already have access to internal networks.

This article is about Diagnosing whether this is your case and showing you alternate Solutions for debugging your webhooks or setting up webhooks to access the local network.



  • Administrator role in FogBugz



FogBugz On-Premises will reject as "Unacceptable URL" any webhook requests targeting hosts having the following IP addresses or domains:

  • all IPv6 addresses
  • the and IPv4 ranges (class A private network)
  • the following domains: localhost, fogbugz.com, fogcreek.com, kilnhg.com, fogcreek.local, fogcreek.com, copilot.com.




Use class C private network

The (class C private network) range is allowed by the local traffic detection mechanism. If your webhooks try to access hosts having IP addresses from this range, FogBugz On-Premises will execute the requests.


Use an external site for webhook debugging

As an alternative, you could use external websites, like Webhook.site or RequestBin.com to try out your FogBugz webhooks and check their payloads.


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