Business Phones Not Working
When every extension goes silent at once, it's rarely the phones themselves.
A full office outage — every desk phone dark, no dial tone anywhere — almost always traces back to something upstream of the handsets: power, a switch, or the connection to your carrier. Here's how we narrow it down fast.
Likely causes
Ranked from most to least common based on what we see in the field.
- PoE switch or power supply failure feeding the phones
- ISP outage or SIP trunk down at the carrier
- SIP registration expired on the PBX or gateway
- Firewall or router rule blocking SIP/RTP traffic
- Failed trunk or station card on a legacy PBX
- MAC or programming change that broke a shared configuration
- Cabling or punch-down fault at a shared patch panel
What you can check first
Safe steps that take a few minutes and can save a truck roll.
- Check whether the PoE switch has power and its status lights are normal
- Check your router/modem's WAN light — if it's off, it's an internet issue
- Confirm your ISP's status page or app for a reported outage
- Reboot in order: modem/ONT first, then router, then PoE switch, then phones
- Try a single handset in a different jack to isolate a cabling fault
How we diagnose it
We start upstream and work down: internet and carrier connectivity, then the PBX or SIP gateway's registration status, then power to the switch, then individual cable runs. This order finds shared-cause outages in minutes instead of chasing one phone at a time.
Getting you back online
If it's a power or switch failure, we can often swap hardware onsite the same day. If it's carrier-side, we escalate with your provider and provide a temporary failover route where available so calls keep coming in while it's resolved.
- Emergency onsite dispatch across all five boroughs
- Loaner or replacement PoE switches when hardware has failed
- Carrier escalation for SIP trunk or ISP-side outages
- Temporary call forwarding so you don't miss incoming calls
Frequently asked
Why did all our phones go down at the same time?+
A single shared failure point — a PoE switch, your internet connection, or your SIP trunk — took every phone with it, since they all depend on the same power or connection.
Can this be fixed remotely?+
Sometimes. If it's a SIP registration or configuration issue, we can often fix it remotely. Power and hardware failures need someone onsite.
How fast can someone get to our office?+
Call 332-216-4296 and we'll get a technician scheduled as soon as possible based on your location and current availability.
We service all five boroughs
Onsite diagnosis and repair across New York City.
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