9 common network issues and how to fix them
Common home and office network issues include poor Wi-Fi, slow speeds and hardware problems. Fixes involve upgrading equipment, reducing congestion and updating systems.
When the COVID-19 pandemic hit, employees worldwide began working from home. Employees who had relied on network technicians now had to troubleshoot issues themselves.
Now, five years after the pandemic, many organizations have mandated employees to return to the office. In many cases, employees have been required to return only on specific days while working at home the rest of the week. Other employees have been tasked to return for all five days of the full work week.
Whether in the office all or part of the week, employees can run into several common network problems regardless of location. This article outlines the top problems likely to occur both in the office and at home and offers ways to fix them.
1. Poor network performance at home
Poor performance is a major contributor to network problems. In some cases, performance limitations are the main cause. Most network providers offer a range of performance options, with higher options at higher monthly prices. Moving to a higher-rated option might increase network performance. If it doesn't, then the problem could be more complex.
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What is network management?
Next, examine the router. A router adequate for browsing the web might not be sufficient for a meeting with many participants speaking simultaneously. The fix might be as simple as replacing the existing router with one with higher capabilities, although often at a higher price.
If the distance between the router and the work area causes a weak Wi-Fi signal, the fix might be as simple as moving the router. An obstruction, such as a wall or large object, might block the signal. In the case of a large obstruction, such as a home freezer, the fix might be to place the router higher, enabling the Wi-Fi signals to pass over the obstruction.
Other fixes include the following:
- Move the router closer to the work area.
- Add a repeater closer to the work area.
- Connect the router to the computer with an Ethernet cable.
Network congestion can be another problem for home networks, especially when two or more people share the line and both generate traffic. In that case, it might be necessary to have two or more separate lines.
Devices such as microwave ovens, cordless phones and Bluetooth devices might also interfere with Wi-Fi signals. Without a network test tool, it can be difficult to identify the source of the problem.
2. Slow network
Several factors can slow an office network that previously performed adequately. For example, if administrators add a new application to the network, such as video conferencing or online training videos, this can increase bandwidth consumption and cause congestion. Another cause of congestion can occur when a failing switch port or link causes traffic to route around the failure and overload another link.
More issues can occur if the network is part of a larger organizational network. A change in the larger network can result in more traffic through the internet connection point, thus slowing responses to cloud-resident applications.
3. Weak office Wi-Fi signal
Wi-Fi signal strength can be adequate in most office areas, but weak or nonexistent elsewhere. If a company decides to rearrange its office area, a wireless connection can weaken where signal strength had been sufficient before the move. For example, a large metal object, such as a file cabinet, can block the Wi-Fi signal.
4. Physical connectivity issues
Physical connectivity issues can also disrupt network connectivity. A common problem occurs when a network cable becomes damaged or knocked loose when network administrators add or remove cables from a switch, or when one of the other cables accidentally disconnects. Cables can also become damaged if someone pulls them around a sharp edge.
5. Excessive CPU usage
Use Task Manager to find an application consuming a high proportion of system resources, such as CPU, memory or disk space on home and office networks. That requires simultaneously running Task Manager and the program that consumes excessive system resources. Task Manager can show applications that network administrators might not realize are running in the background. Upon notice of this, edit startup files to remove unneeded programs.
An application that has been running for a long time can slowly leak resources. To improve performance, stop and restart the application, which sometimes requires stopping and restarting the entire system and updating device drivers. Finally, since viruses also consume resources, keep antivirus software up to date.
6. Slow DNS lookups
DNS translates the common name that identifies a server or service into the IP address used to route a network request. For commonly used names, the system's DNS cache likely stores the match, so the lookup is quick. For less commonly used names, the matchup can be stored in a more distant cache, such as the root server for the top-level name, e.g., .com or .org, or a national root, such as .uk.
Each DNS server along the path checks its cache before making a request to the next server. The next server then checks its cache and continues the process. The lookup can take a long time due to a slow link along the path or a slow or overloaded server; to address this issue, network administrators can reconfigure local routers to shift requests to a faster chain of servers.
Slow DNS is only a problem when used once when a program first starts. But it can be a problem when used many times to invoke remote programs.
7. Duplicate and static IP addresses
Two systems can't share the same IP address in a network. If the network detects duplicate IP addresses, neither system can access the network reliably. Network administrators can use Dynamic Host Configuration Protocol to assign IP addresses to most network devices. DHCP maintains a pool of addresses assigned to the local network and assigns a different address from the pool to each system.
DHCP can't assign permanent IP addresses to workstations, but it can assign them for a limited time. Workstations request new addresses before the time runs out, although they usually receive the same address. If a workstation shuts down before requesting a new address and time runs out, it loses the address and could receive a different one upon startup.
External systems can't receive updates if the network address changes. To fix this, network administrators can assign static IP addresses to some network devices, such as printers or web servers.
Another issue can occur when users set up private web servers and assign a static address to support their hobbies without informing network administrators. If the static address is also in the pool of addresses that DHCP assigns, two devices will end up sharing the same address. Attempts to access either device can reach the wrong one, and the network will fail.
8. Printer connection issues
When users can't connect to a printer, first check whether the printer is plugged in, turned on and has paper. The printer should appear on the Devices and Printers panel in Windows. If it does, check whether the print job is in the queue.
Users might need to stop and restart the print spooler, i.e., the software that stores files until they are ready to print. Also, check the printer vendor's website for a downloadable app to diagnose and fix problems.
If the OS has been recently upgraded, network teams should identify if other users have similar problems. Check Microsoft's website to see whether the company has identified a problem. Network administrators can also restart the printer and the system.
Finally, administrators should update printer drivers and the OS, including connecting wireless printers to the Wi-Fi signal in order to receive a connection to the network. In some cases, that could require temporarily shutting down the antivirus software.
9. VPN issues
VPNs are used most often to connect home networks to the office when sensitive data is exchanged. They are also used when sensitive data is exchanged with remote offices or corporate partners.
Failure to connect is one of the most common VPN problems. Network teams should check whether users have successfully logged in to the service by entering the correct credentials and ensuring that accounts are up to date. Administrators should also check firewall settings by opening some ports or checking the problem by temporarily shutting down the firewall.
Troubleshooting common network issues
Since networks are complex, problems can occur for a variety of reasons. This article explored some of the most common potential network problems. For other, more complex issues, administrators should scan the web for help or contact network service providers and device vendors for support.
In addition, network administrators should continuously monitor their networks and stay up to date with hardware and software updates to prevent issues before they occur. No network is immune to problems, however, and every system can experience vulnerabilities. If issues do arise, administrators can follow a list of best practices to address issues and further safeguard the network.
Editor's note: This article was updated to improve the reader experience.
David Jacobs has more than 30 years of networking industry experience. He has managed leading-edge hardware and software development projects as well as consulted Fortune 500 companies and software startups.
