What Causes Slow Computer Download Time?

By Jason Artman

A slow download speed can be frustrating.
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Home Internet connections in many cities have come a long way since the days of dial-up connections. Today, many people have access to broadband Internet connections that can download data at several megabits per second. If you are accustomed to nearly instantaneous downloads, it makes a slow download speed all the more annoying. Although many causes of slow download speeds are beyond your control, there are some causes that you can correct yourself.

Malicious Software

Malicious software consumes system resources. Additionally, some viruses periodically utilize the Internet connection of the infected computer to report on the user's activities. This can cause a slowdown of the Internet connection. If your computer has no antivirus software installed, installing an antivirus program and scanning the computer completely should be one of your first steps in troubleshooting an Internet connection issue.

Internet Service Degradation

Internet Service Providers (ISP) have a limited amount of bandwidth that all users must share. If many users are online downloading files simultaneously, it can cause congestion and degraded service. This is particularly likely to happen if the ISP experiences a problem on one section of their network and must temporarily route some users to another section of the network. ISPs know when network outages occur, so it is generally best to try the download again later rather than calling technical support.

Uploading While Downloading

Most Internet connections are asynchronous, meaning that they download and upload data at different rates. In most cases, the upload rate is much slower than the download rate. When you upload a large file, it can saturate the bandwidth of your Internet connection and cause downloads to be very slow. When you upload a file, it is generally best to let the transfer finish before downloading files.

Background Programs

Your download speed can be temporarily reduced when a background program accesses the Internet. The Windows Update application is a common example of this; Windows Update scans the Internet for critical security updates periodically, downloading them automatically as they become available. If a background program is downloading data, it may appear that your Internet connection is running slowly. Check the Notification Area in the lower-right corner of the screen to see if any background programs are downloading data.

Remote Site Issue

Often, what appears to be a slow download speed on your computer may actually be the result of a problem with the website that you are downloading from. For example, when a major news event occurs or a software company releases an important update, the website can experience slowness or even be brought down temporarily as many people rush to access it. If you experience slow download speeds at only one website, try the download again later.

Poor Wireless Signal

A wireless Internet connection only transfers data at the highest possible speed when the signal strength is excellent. Check the signal strength of your wireless connection using the signal meter in the bottom right corner of the screen. If you are on a home network, move your computer closer to the wireless access point. If you use a cellular service for your wireless Internet, you may be in an area where the coverage is poor.