Shut down the computer and restart it. If you see an I/O error only once, restarting the machine may fix it without further action. Sometimes, the Windows SWAP file, or temporary cache file, may become corrupted by spyware or poorly written software that writes too much data or reduces the size of the SWAP file temporarily. If this occurs, Windows may report an I/O error stating it cannot read or write data to the "C:" drive. Restarting the computer flushes the temporary cache files and fixes the problem. However, you should run your anti-malware or antivirus software after restarting the computer to avoid software related I/O errors in the future.
Update the device driver for the drive or storage device if restarting the computer does not fix the I/O errors. Open a Web browser and visit the support website of the manufacturer of the drive or storage device. Download the latest Windows driver for the device and save it to your computer. Open Windows Explorer, double-click the download file and then follow the prompts to install the updated driver on your computer. Restart the computer after updating the device driver and then use the machine normally to see if it corrected the I/O error problems.
Run the Windows Chkdsk tool to see if the drive or storage device has bad sectors or media causing the I/O errors. To run Chkdsk, click the Start button, then type "Chkdsk /R Z:" where "Z:" is the drive letter of the drive or storage device causing the I/O errors. Press the "Enter" key to run the utility in a new Command Prompt window. Windows prompts you to run the utility when you restart the computer because it cannot gain exclusive access the drive or device. When prompted press "Y" to restart the computer. Windows shuts down the computer and restarts it. After the computer restarts, the Chkdsk command line utility launches automatically and scans the disk for errors. If the utility finds bad sectors or other problems with the drive, it attempts to repair them automatically. After the Chkdsk utility finishes scanning and repairing the drive, the computer restarts and boots into Windows.
Check the cable connection for the drive or storage device. If the device is an external hard drive or optical drive, disconnect and reconnect its USB data cable and see if that corrects the I/O problems. If the device is an internal drive, shut down the computer and disconnect all external cables, and then use the Phillips screwdriver to remove the side panel or access cover. Check the cable connections for all of the drives in the computer and ensure they are tight and secure. Check the connections on the rear of the drives, as well as on the motherboard. When checking the cable connections, check the power cable connections from the power supply as well.