On older single-processor computers or computers with demanding network applications or network devices (wifi is a good example), the network can interfere with proper operation of files, resulting in Computer speed issue errors.

It is sometimes insufficient just to unplug the network, sometimes the network hardware must be disabled.

• Enter the device manager the same way as is done in verifying the drivers
• Find the network hardware
• Right click the network hardware and click disable

If this solves the problem with running files, consider replacing the piece of hardware with a higher performance unit that demands less of the system CPU.