What you’re seeing
- Every computer, phone and printer in the office loses connectivity at the same moment.
- Switch lights blink rapidly and continuously on many ports at once.
- The outage started right after someone connected a cable, a desk switch or a new device.
- Network equipment becomes unresponsive or extremely slow to manage.
- Unplugging a specific cable makes everything work again almost instantly.
Common causes
Every environment is different, but these are the causes our engineers find most often:
- A cable connects two ports on the same switch or network, creating a loop that endlessly repeats traffic.
- Spanning Tree Protocol is disabled, misconfigured or not supported on an unmanaged desk switch.
- A device such as a VoIP phone or docking station bridges two network ports together.
- A faulty network adapter or switch is sending a constant flood of broadcast traffic.
- Loop protection features like storm control or BPDU guard are not enabled on access ports.
Why it matters
A switching loop can take down an entire office within seconds. Phones go silent, card terminals stop processing, cloud apps freeze and servers become unreachable. Because the cause is often a single cable, it's easy to reintroduce: the outage ends when the cable is unplugged and returns when someone plugs it back in. Repeated full-network outages cost lost sales and staff time and can also disrupt security cameras and access control systems that depend on the same network.
How AskTechGurus fixes it
Skip the trial and error. A certified engineer works on your actual system, finds the root cause, and fixes it properly.
Tell us what’s happening
Submit a ticket in about two minutes. Paste the error, describe what changed, and pick your tier. No charge to submit.
A certified engineer diagnoses it
A vetted, US-based systems engineer claims your ticket, usually within minutes during business hours, and investigates over a secure remote session you can watch and end at any time.
Fixed and verified with you
The engineer resolves the root cause and confirms with you that it’s working. You don’t just get a workaround, and you get a plain-English summary of what was wrong.
Pay only when it’s resolved
Fixed price from $99, invoiced only after you approve the fix. If it isn’t resolved, you don’t pay.
Frequently asked questions
Can one cable really take down the whole network?
Yes. A loop makes traffic circulate endlessly, overwhelming switches and every device connected to them.
How do we stop it happening again?
Switches can be configured to detect and shut down loops automatically. An engineer can review your equipment remotely and explain what protection is possible.
Is this a cyberattack?
Almost always not. Loops and broadcast storms are usually caused by cabling mistakes or faulty hardware, though we confirm the cause before ruling anything out.