What you’re seeing
- New laptops, phones or visitors cannot connect, while devices already online keep working.
- The DHCP server logs warnings that the scope is full or has no free addresses.
- Affected devices fall back to a 169.254 address or show "no internet".
- The problem is worse on busy days, after events or when many guests are in the office.
- The address list shows many leases for unknown phones, smart TVs or IoT gadgets.
Common causes
Every environment is different, but these are the causes our engineers find most often:
- The scope is too small for the number of devices, often a single small range sized years ago.
- Lease times are long, so addresses stay reserved for devices that left days ago.
- Phones and laptops use randomized MAC addresses, so the same device can consume several leases.
- Guests, IoT devices and staff share a single network instead of being separated.
- A rogue or misbehaving device is requesting many addresses, deliberately or through a fault.
Why it matters
When the address pool runs out, the people affected are often the most visible: new hires on day one, visiting clients and executives arriving with a new device. Meanwhile, IoT gadgets and guest phones quietly occupy addresses meant for business equipment. Mixing guests and staff on one network is also a security concern, since visitors end up on the same network segment as your servers and file shares. Right-sizing and separating networks improves both reliability and security.
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't we just make the range bigger?
Sometimes, but it often requires changing the network's addressing, which affects other settings. An engineer reviews the whole picture first so nothing else breaks.
Should guest devices be on a separate network?
In most businesses, yes. Separating guests and IoT devices frees addresses and keeps visitors away from company systems.