--- title: "SIP 404 Not Found" url: "https://enfonica.com/help/sip-errors/404-not-found" summary: "On an outbound call, a 404 means that the phone network that serves the number says it doesn't exist. Check the number and its format, and try it from a mobile. On an incoming call, the 404 usually comes from your own PBX or Microsoft Teams, because it doesn't recognize the number it was sent." type: error audience: everyone products: ["Cloud SIP", "Phone Numbers", "Teams Direct Routing"] works_with: ["Any SIP PBX or SBC", "Microsoft Teams Direct Routing"] who_can_do_this: "Whoever manages your PBX and your Enfonica project" --- # SIP 404 Not Found **Short answer:** On an outbound call, a 404 means that the phone network that serves the number says it doesn't exist. Check the number and its format, and try it from a mobile. On an incoming call, the 404 usually comes from your own PBX or Microsoft Teams, because it doesn't recognize the number it was sent. **Applies to:** Cloud SIP, Phone Numbers, Teams Direct Routing **Works with:** Any SIP PBX or SBC, Microsoft Teams Direct Routing **Who can do this:** Whoever manages your PBX and your Enfonica project First check the [Enfonica status page](https://enfonica.status.io/) for a known incident. ## Outbound calls to a number fail with 404 Not Found What you see: `SIP/2.0 404 Not Found` Cloud SIP accepted the call and passed it to the phone network. The network that serves the number then answered that the number isn't assigned. The response usually carries a `Reason` header with `cause=1` and the text `Unallocated (unassigned) number`. In **Cloud Voice > Calls**, the leg to the phone network shows the error code `ENDPOINT` and the message `The endpoint is not connected`. ### The number is disconnected or doesn't exist **To check**, call the number from a mobile. If it also fails, or you hear a recorded announcement, this is the cause. **To fix it**, check the number with whoever gave it to you. If you dial from a list, mark the number as disconnected. ### Your PBX changed the number on the way out An outbound rule that drops or adds a digit can turn the number dialed into a different number. The new number looks valid but isn't in service. A 1300 number is the usual case. **To check**, open the call in the Console, and compare its **To** number with the number the user dialed. For example, 1300 975 707 sent as `+61300975707` instead of `+611300975707`. **To fix it**, correct the outbound rule (dial plan) in your PBX so that it sends the number in full international format (E.164). For examples of every kind of number, see [Which number format should my PBX use?](https://enfonica.com/help/sip-trunking/number-formats) ## Calls to a number fail with 404 only from one caller ID What you see: `SIP/2.0 404 Not Found` Some networks refuse calls that present particular caller IDs, to protect their customers from scam and spoofed calls. They answer with a 404 rather than a clearer code. ### The destination network is refusing the caller ID **To check**, call the same number with a different caller ID. If the call works, this is the cause. It's most common on forwarded calls, where your PBX passes the original caller's number through. **To fix it**, present one of your own numbers on these calls. If you need the original caller's number to show, contact us with an example, and we'll look at the options for your setup. ## A number works from a mobile but fails with 404 through Enfonica What you see: `SIP/2.0 404 Not Found` Sometimes a number is in service and rings from a mobile, but calls through Enfonica get a 404, whatever caller ID you use. This means the network that serves the number has a fault with calls that arrive from other carriers. ### The destination network has a fault **To fix it**, contact us, because this is something we raise with the network. Send us two or three example calls with the details listed below, including a time when the number worked from a mobile. We'll trace them and take it up with the network responsible. ## Incoming calls fail with 404 from your PBX or Teams What you see: `The endpoint is not connected` On an incoming call, Enfonica delivered the call, and your own system answered 404 because it doesn't recognize the number. In **Cloud Voice > Calls**, the leg to your PBX or Teams shows the error code `ENDPOINT` with this message. The SIP trace shows the 404 coming from your system's address. ### Your PBX doesn't have the number set up Enfonica sends the number that was called in E.164 format, for example `+61255501234`. Your PBX's DID (the number it answers on) or inbound rule must match it in that format. **To check**, look at your PBX's DIDs and inbound rules. This is the cause if the number is missing, or if it's listed in another format, such as `0255501234`. **To fix it**, add the number in E.164 format, with its leading `+`, and give it an inbound rule. For this and the other ways a PBX rejects calls, see [Calls aren't reaching your PBX](https://enfonica.com/help/call-troubleshooting/inbound-calls-not-arriving). ### The number isn't set up in Microsoft Teams Teams answers 404 when the number isn't assigned in your Microsoft 365 tenant. Callers might hear a busy tone. **To fix it**, ask your IT team or MSP to check these settings in your Microsoft 365 tenant: - The user has a Teams Phone license. - The number is assigned to the user in E.164 format. - The user has a voice routing policy. For the full checklist, see [Teams Direct Routing calls fail or don't ring](https://enfonica.com/help/teams-direct-routing/teams-calls-not-working#incoming-404). ## How do I tell where the 404 came from? Open the call in **Cloud Voice > Calls**, and read its SIP trace: - If the 404 came back from the phone network, the call was outbound, and the causes in the first three sections apply. - If the 404 came from your PBX's or Teams' address, it's an incoming call that your system refused. To learn how to read the trace, see [Find a call and read its SIP trace](https://enfonica.com/help/call-troubleshooting/find-call-sip-trace). For every other error on outbound calls, see [Outbound calls aren't going through](https://enfonica.com/help/call-troubleshooting/outbound-calls-fail). ## What to send us Include these and we can find the call straight away. - The number that made the call and the number it called, in full international format (for example +61255501234). - The date and time of the call, with your timezone. - Whether the call was inbound or outbound. - The call ID, if the Console shows the call. - What happened: an error message, silence, a busy tone or a dropped call. [Contact support](https://enfonica.com/contact-support?article=%2Fhelp%2Fsip-errors%2F404-not-found&topic=call-fault) ## Related - [Outbound calls aren't going through](https://enfonica.com/help/call-troubleshooting/outbound-calls-fail.md) - [Calls aren't reaching your PBX](https://enfonica.com/help/call-troubleshooting/inbound-calls-not-arriving.md) - [Teams Direct Routing calls fail or don't ring](https://enfonica.com/help/teams-direct-routing/teams-calls-not-working.md) - [Which number format should my PBX use?](https://enfonica.com/help/sip-trunking/number-formats.md) - [Caller ID problems: wrong number, private calls, rejected, or spam](https://enfonica.com/help/caller-id/caller-id-problems.md) - [Find a call and read its SIP trace](https://enfonica.com/help/call-troubleshooting/find-call-sip-trace.md) --- Web version: https://enfonica.com/help/sip-errors/404-not-found