Why does my phone keep connecting and disconnecting from computer?

Connecting a phone to a computer via USB is a common way to transfer files, photos, music, and more between devices. However, many users experience frustrating issues with their phone repeatedly connecting and disconnecting while plugged into their computer.

There are several potential causes for a phone connecting and disconnecting, including faulty cables, outdated drivers, insufficient power to the USB port, software glitches, an outdated operating system on the phone, transferring too much data at once, and physical damage to the charging port. This article explores the main reasons a phone may keep connecting and disconnecting and provides troubleshooting tips to resolve the issue.

Faulty USB Cable

A faulty or damaged USB cable is one of the most common reasons for intermittent connectivity issues between a phone and computer. USB cables contain small, delicate wiring and circuitry that can easily become damaged over time from frequent bending, pulling, and daily wear and tear.

As USB-C cables age and degrade, the tiny connector pins inside the cable tip can bend or break, disrupting the electrical contacts required for steady power and data transfer. Damage to the wires or joints inside the cable also introduces resistance and connection dropouts. USB-C cables with thin, lightweight builds seem especially prone to premature failure.

Signs of a faulty USB cable include a loose-fitting connection, intermittent charging, random connectivity losses, and significantly slower syncing speeds. Some users report problems after a cable gets kinked or bent at extreme angles only one time, indicating internal damage. Any cable exhibiting these issues should be replaced.

While performance may degrade over time, a quality USB-C cable made with thick, durable cabling and reinforced connectors should provide reliable connectivity for 1-2 years or more of regular use before needing to be replaced. Selecting premium USB cables, handling them with care, and avoiding damage can maximize longevity.

If phone connection issues persist after swapping in a brand new high-quality cable, the problem likely lies with the phone or computer rather than the cable. But in most cases of intermittent connectivity problems, a faulty USB cable ends up being the culprit.


Outdated Drivers

Outdated or corrupt drivers on the computer are a common culprit for connection issues between a phone and computer. As drivers become outdated, they can cause a range of problems including connectivity failures and instability. According to MinITool, “these outdated drivers can cause graphics output, video resolution, and Internet connectivity issues” (source). iolo also notes that “As device drivers become old and obsolete, they cause a number of computer functionality symptoms, including system freezes, malfunctioning devices, video game crashes, and connectivity problems.”

When drivers are not up-to-date, they may not be optimized to work properly with the latest hardware and operating systems. This can prevent the computer from recognizing or maintaining a connection with the phone. Updating all drivers, especially USB, chipset, and Bluetooth drivers, can often resolve intermittent connectivity problems and crashes. Keeping drivers updated ensures maximum compatibility and performance when connecting a phone to a computer.

Insufficient Power

One common reason a phone may keep disconnecting and reconnecting from a computer is insufficient power or electricity from the USB port. Mobile phones require power to charge and operate, which they draw from the connected USB port. If the USB port cannot provide enough steady power, the phone may disconnect as it tries to pull more electricity than the port can handle.

USB ports on computers have limitations on how much power they can deliver, especially older ports like USB 2.0. Newer phones with fast charging require more power – in some cases up to 2 amps or more. If the USB port is only designed for 0.5 amps, it will struggle to meet the phone’s power demands.

As the phone tries to draw more current than the USB port can provide, the voltage may drop or fluctuate, triggering the phone to disconnect momentarily before reconnecting. This cycle repeats as the phone tries in vain to pull sufficient power from the underpowered port.

Solutions include using a wall charger to directly power the phone during data connections, connecting to a higher-power USB 3.0 port, or using a USB hub with its own external power source. Ensuring the USB port and cable are not damaged or worn also helps provide steady power delivery.

In some cases, the computer may run out of free USB power budget as devices get added. Disconnecting other USB devices that aren’t needed can free up power delivery for the phone.


Wireless interference from other devices using the same frequency can disrupt the connection between your phone and computer [1]. Nearby routers, Bluetooth devices, microwaves, cordless phones, and other electronics can all contribute to interference. This interference causes signal degradation, lag, disconnections, and other connectivity issues [2].

The 2.4GHz band is especially prone to interference since many common household devices operate on this frequency. Bluetooth and older WiFi networks use the 2.4GHz band. Newer devices may use 5GHz which experiences less interference. However, even 5GHz networks can still be impacted by interference from other 5GHz networks or devices [3].

To reduce interference, try changing the WiFi channel on your router, updating devices to use 5GHz if possible, or increasing physical distance between devices. Proper antenna positioning can also help optimize signal quality. In severe cases, switching to a wired Ethernet connection may be required for a stable connection.

Software Glitches

Software issues are a common cause of intermittent connectivity problems with phones. Glitches in the operating system, apps, services and firmware can disrupt the ability of the phone to maintain a stable connection with other devices.

One example is bugs in the Android or iOS operating system that affect the USB or wireless interfaces. These may prevent the phone from properly recognizing or communicating with connected devices like computers. OS bugs can also cause random connectivity drops, lag and freezes.

Similarly, poorly coded or outdated apps can conflict with connectivity services running in the background. For instance, a rogue app may hog too much memory, CPU and network resources, hampering wireless radios and connections.

Problematic firmware updates are another source of software-related connectivity issues. Vendor firmware controls the low-level hardware like Wi-Fi and cellular modems. Faulty firmware can clearly break or slow down these connections.

Finally, bugs in mobile services like hotspot tethering, screen mirroring and file transfers can also interfere with maintaining steady connections between the phone and external devices.

Restarting the phone and uninstalling problematic apps often resolves transient software glitches affecting connectivity. Upgrading to the latest OS, firmware and apps can fix more stubborn bugs causing connection issues.

Outdated OS

One common culprit behind frequent disconnects between a phone and computer is an outdated operating system (OS) on one or both devices. As the Risks of Using Outdated Operating System points out, old OS versions often lack support for new hardware and connectivity protocols. Over time, critical security updates, bug fixes, and feature improvements stop arriving for antiquated OSes.

For example, an older Windows OS like Vista or XP on a computer may not fully support connecting to newer Android phones over USB. There could be missing drivers, limited USB transfer speeds, or general software incompatibilities. Similarly, a many-years-old Android version on a phone may not work smoothly with file transfers and connections to a Windows 10 laptop. The outdated OSes on either device essentially speak different languages and struggle to communicate efficiently over USB.

Frequent disconnects can occur as the unsupported devices fail to maintain a steady connection during data transfers or software/firmware updates. While an outdated OS may not completely prevent connectivity, it introduces instability and interruptions. Upgrading to newer OS versions on the phone and computer is recommended to enable reliable, consistent connections over USB.

Too Much Data Transfer

Transferring large amounts of data between your phone and computer can sometimes overwhelm the connection and lead to disconnects. The USB cable and ports have a maximum bandwidth that they can support. If you try to transfer files that exceed that bandwidth, it puts a strain on the connection.

For example, transferring multiple gigabytes worth of photos, videos, or other files between your phone and computer may be more data than the USB cable can reliably handle at one time. This can cause the phone to disconnect or the transfer to fail intermittently as the data overwhelms the connection capacity.

If you notice your phone disconnecting or transfers failing only when moving large amounts of data, try transferring smaller batches of files at a time rather than one huge transfer. Or use a cloud storage service to sync the files instead of transferring directly over USB. This prevents too much data from burdening the USB connection at once.

You can also try different USB cables, ports, or hubs to see if another connection offers higher bandwidth that can handle your data transfers without disconnecting. Limiting or throttling the transfer speeds in your phone’s settings may help as well if data overload seems to be the culprit.

Overall, be mindful of how much data you are trying to move at one time over USB, as transfers that exceed the bandwidth limitations can lead to intermittent disconnect issues in some cases. Adjusting your transfer approach can help minimize connection interrupts.



Physical Damage

Physical damage to the USB port or charging port can prevent a steady connection between your phone and computer. Repeated plugging and unplugging of cables can wear down the ports over time. Debris and pocket lint can also accumulate in the ports, obstructing the connection.

Inspect the ports on both your phone and computer for any signs of damage. Look for bent pins, chipped plastic, or other abrasions around the port. Even minor imperfections can disrupt connectivity. Try cleaning out the ports with compressed air to dislodge any debris.

If the damage is severe enough, you may need to replace the USB port or charging assembly on your phone. Repair guides and parts can often be found online for common phone models. In some cases, it may be more cost effective to simply replace the phone, especially if it’s an older model.

Avoid forcing cables into damaged ports, as this can cause further damage. Be gentle when plugging and unplugging cables. Consider wireless file transfer as an alternative if the ports are unusable.

To prevent port damage, remove cables carefully by pulling straight out instead of yanking. Don’t bend cables at sharp angles. Avoid exposing your phone to drops, spills or other impacts that could potentially damage the ports.


In summary, there are several common reasons why your phone may keep connecting and disconnecting from your computer, including a faulty USB cable, outdated drivers, insufficient power supply, software glitches, an outdated operating system, interfering signals, too much data transfer, and physical damage to the port or cable. To troubleshoot, first try different cables, ports, computers, and USB modes. Update your drivers, OS, and phone software and disable unnecessary apps and features. If the issue persists, try reducing the amount of data transfer, clearing app caches, restarting your devices, or getting professional phone or computer repair. With some diligent troubleshooting, you should be able to resolve any connectivity issues between your phone and computer.