A+ Lab 6 — No Network: Adapter, IP, or Gateway?

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CompTIA Cyber Path • A+ Lab Series • Lab 6

A+ Lab 6 — No Network: Adapter, IP, or Gateway?

This lab trains one of the most common support tickets: “My internet isn’t working.” Your job is to stop guessing and isolate whether the real problem is the network adapter, the IP configuration, or the gateway / router path.

Simulated Ticket

User reports: “I can’t get online. Nothing loads.”

Priority: High • Scope: Single workstation first • Goal: determine whether the failure is caused by a disabled adapter, bad/missing IP settings, or loss of gateway connectivity.

Time + difficulty:

⏱ 25–35 minutes • 📊 Beginner / early A+ • Goal: check layer by layer instead of randomly rebooting things.

A+ aligned Basic networking Help desk workflow Local progress saved
Progress: 0%

What a Real Tech Should Ask First

  • Is this one device or multiple devices?
  • Are they on Wi-Fi or Ethernet?
  • Does the adapter show connected, disabled, or disconnected?
  • Does the system have a valid IP and default gateway?

Print mode auto-shows all steps and hides the hero diagram + progress UI.

No Network
Check Link / Adapter
Enabled? Connected? Airplane mode?
Check IP
Valid address? DHCP? APIPA?
Check Gateway
Reach router? Local path alive?
Adapter Issue
disabled / unplugged
IP Issue
bad DHCP / no config
Gateway Issue
router / path failure
Good troubleshooting moves from local device → addressing → gateway path.

What You Need

System
Setup
  • A Windows PC, laptop, or VM with network access
  • Either Ethernet or Wi-Fi available for testing
Focus
Goal
  • Check adapter state
  • Check IP configuration
  • Check gateway reachability
Common mistake:

Don’t jump straight to “the internet is down.” First determine whether the PC even has a working adapter, a valid IP, and a reachable local gateway.

Real-World Translation

Why this matters:

Network tickets show up everywhere: offices, warehouses, clinics, schools, and remote users working from home.

A real tech follows a simple chain: adapter → IP → gateway → internet/test destination.

Break / Diagnose / Fix

Break
Simulate Network Failure

Create a safe network problem you can isolate.

Option A — Adapter problem

  1. Disable the network adapter in a safe lab environment.
  2. Or disconnect the Ethernet cable / disconnect Wi-Fi.
  3. Observe the system icon and adapter state.

Option B — IP configuration issue

In a lab, use an invalid static IP, remove DHCP, or create a state where the PC cannot receive a valid address.

Option C — Gateway/path issue

Keep the adapter up with a valid IP but break the local path to the router or test against a disconnected virtual network segment.

Confirm the symptom

You should see one of these patterns: no link, bad/missing IP, or inability to reach the default gateway.

Diagnose
Adapter / IP / Gateway

Work from the workstation outward instead of guessing.

Check in this order

  1. Confirm whether the adapter is enabled and connected.
  2. Check IP settings using ipconfig or network settings.
  3. Look for a valid default gateway.
  4. Ping the gateway before blaming the internet.
  5. Then test an outside destination if the gateway responds.

What healthy vs broken looks like

  • Healthy adapter → enabled, connected, proper link state
  • Adapter issue → disabled, unplugged, Wi-Fi disconnected, airplane mode, driver issue
  • Healthy IP config → valid address, subnet mask, gateway present
  • IP issue → no IP, wrong static IP, missing gateway, or APIPA address like 169.254.x.x
  • Gateway issue → PC has good local config but cannot reach the router/default gateway

Look for clues

  • Does the problem affect only one device?
  • Did someone unplug the cable or disable Wi-Fi?
  • Is the IP from DHCP or manually assigned?
  • Can the machine ping itself, then the gateway, then another host?
Example logic:
1. Check adapter state
2. Check IP address
3. Check default gateway
4. Ping gateway
5. Test beyond gateway
Fix + Verify
Resolution

Restore connectivity and verify the user can actually reach what they need.

Possible fixes

  1. Enable the adapter or reconnect Ethernet / Wi-Fi.
  2. Renew DHCP or correct the static IP configuration.
  3. Restore or correct the default gateway value.
  4. Restart the adapter or networking stack if needed.
  5. If the PC is healthy but the gateway fails, escalate to router/switch/network path troubleshooting.

Useful checks

  • ipconfig
  • ipconfig /release then ipconfig /renew
  • ping 127.0.0.1
  • ping [default gateway]

Verify

  • Confirm the adapter is up and connected
  • Confirm a valid IP and gateway are present
  • Confirm the gateway responds
  • Confirm the user can reach their required destination
Technician habit:

“Internet works” is too vague. Prove it in layers: adapter up, valid IP, gateway reachable, then successful outside access.

Expected output / success signs

  • Valid IP configuration is present
  • No APIPA-only address unless that is expected in lab design
  • Gateway responds to ping when appropriate
  • User reports restored connectivity

Write the ticket note

Use: Symptom → Checks → Actions → Result

What This Skill Maps To

  • Basic network troubleshooting methodology
  • NIC / adapter awareness
  • IP addressing fundamentals
  • Gateway path testing
  • Ticket documentation discipline

Self-Check Quiz (Unlock Next Lab)

Score ≥ 75% to unlock the next lab link. Your score is saved on this browser.

1) When a user says “I have no internet,” what is the best first troubleshooting direction?

2) Which IP address range is a strong clue the PC failed to get a normal DHCP address?

3) What should you generally test before blaming the internet provider?

4) Which ticket note is strongest?

Next Lab

🔒 Locked until Quiz ≥ 75% and you Mark Complete
A+ Lab 7 — PC Won’t Boot: Power, POST, or OS?

Tip: update the next lab link when the page exists.

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