Diagnosing (And Fixing) Common Network Problems

Date posted: 8 May 2018 – Category: Cabling Services

While devices today can perform several tasks without going online, internet use remains to be a vital element in business productivity. According to business ISP Beaming, UK businesses lost £7 billion due to internet outages and downtime in 2016. Their study revealed that companies, on average, experienced four outages which then took six hours to be restored each time.

Of these organisations, more than a third completely derailed their productivity, one in ten lost money as soon as internet outage occurred, and almost half took a financial hit after four hours of no internet.

Diagnosing & Fixing Common Network Problems

There are, of course, several effective ways to diagnose your connectivity issues and fix them, which I want to look at in this article.

Resolving Common Network Issues

If you’ve established that the issue is truly on your end—assuming you’ve checked Down For Everyone Or Just Me and following the age-old technical advice of restarting your devices and modem/router—you can then perform the following diagnostics and fixes:

1. A Network Cable Is Unplugged

What Is It:

Before checking various settings and running tests, you should first look at your physical connections. If this is the case, you’ll most likely see a desktop balloon that says “A network cable is unplugged.”

How To Fix It:

Usual causes include bad Ethernet cables, malfunctioning network adapters, or misbehaving network device drivers. To fix these:

Make sure that your Ethernet cable is properly connected to the router and computer.
Is your router flashing green or red lights? Red lights often indicate an ISP issue, so contact their customer hotline.
If your computer has a built-in Ethernet adapter, disable it by double-clicking the desktop balloon error window and choose ‘Disable’ option.
Update your network adapter driver software to its latest version. If it’s using the latest version, uninstall and reinstall the driver to back to its previous version. Go to Control Panel > Device Manager.

If you’re using fibre connection, take extra care as its optic cables often need precise handling using equipment that you may not have lying around. If you see any physical damage (e.g. accidental cutting), contact our professional team to handle it.

2. IP Address Already In Use

What Is It:

If two or more devices are using the same IP address, all those devices will not be able to connect to the network. This creates an IP address conflict and is usually caused by assigning the same static IP address to multiple computers.

If you’re not using static IP addresses, then there could be a malfunction in the network’s DHCP server or your ISP is giving two devices the same dynamic IP address.

How To Fix It:

Check your firewall settings as it may prevent you from connecting to the internet.
Go to Network and Sharing Center > Connections > Click your Wifi name > Properties > internet Protocol Version 4.
If you don’t have a static IP, check “Obtain an IP address automatically” and “Obtain DNS server address automatically”. Do the same for Internet Protocol Version 6.
To check if this works, type cmd in your Start Menu > type: ipconfig > look for the text under Ethernet adapter or Wireless LAN adapter (depending on which connection you have).
If the IPv4 address gives you something like this: 169.x.x.x, then you’re not getting a valid IP address. Type these commands: ipconfig /release and ipconfig /renew.
If this fails, connect your PC directly to your modem using an Ethernet cable. If your Ethernet cable connects you to the internet, then there is an issue with your router.

3. Limited or No Connectivity, Connected With Limited Access, and Intermittent connection

What Is It:

This is often caused by technical glitches or configuration issues on your device or on the path between your device and the network.

Error messages can either say “Limited or no connectivity” or “The connection is limited”. You may also get intermittent connections and/or speed.

How To Fix It:

Start with these simple steps:

Reboot your router, modem, and computer.
Check if you used the correct password (capitalisation, numbers).
Check if you’re connected to the right network and using the corresponding password.
If the router is overloaded (too many users), reboot the router.
Move closer to your router, as thick walls and distance can affect the speed and connection.
Either unplug and reattach your Ethernet cable on both ends or temporarily replace it to see if this is a cable issue.

More advanced steps:

If changing Ethernet cables didn’t work, pull up the command prompt and reset your TCP/IP stack to its original state. To do this, type: netsh int ip reset C:\logreset.txt.
If this first netsh command didn’t work, type the following commands in this order: netsh int tcp set heuristics disabled > netsh int tcp set global autotuninglevel=disabled > netsh int tcp set global rss=enabled.
To verify that above commands worked, type: netsh int tcp show global then reboot your PC.
For Wi-Fi users, your network adapter is most likely going to sleep to conserve power. Disable this by going to Network and Sharing Center > click your Wifi > Properties > Configure > Power Management tab > uncheck Turn off device to save power.
Update the device driver for your network card.
Log in your router and update your wireless security configuration. Set your WPA and security keys if needed.
Connect your computer directly to the modem. If this works, your router may be malfunctioning.

Resume Your Connection

Losing internet connection in the middle of a business day can hamper productivity and affect business’ bottom-line. As a general first step, rebooting your system is often the way to fix plenty of network issues. Afterwards, check physical connections, and then move to your settings. If the issue persists, then your ISP could be the problem.

In any case, all you can do is wait until your connection is back. Continue working on any tasks that do not require internet use and come up with a backup plan to make up for lost time.

If these basic and advanced troubleshooting steps do not work, let us know as you may need a more systemic network maintenance diagnosis.