All of us know that BSOD is the most unexpected error that windows PC users may face. Probably, Most of us are not aware of I/O boot error. If we knew about it, We would keep it in unexpected error list. This problem is not very common. Rarely, A windows user may encounter it. It restricts you to access your PC. It may come in both black and blue screens and show you the error message “An unexpected I/O error has occured”. Like Blue screen of death, It may also show you an error code. Most of the time, The error code is 0xc00000e9. You may see other similar codes instead of it. All of these things indicate that your PC is encountering problem during booting. It is not a new trouble. Many XP, Vista, 7 and 8 users encountered it. But, Recently, I found several windows 10 users experienced this nightmare. I think, It is urgent to know how to fix it.
I/O Error Symptoms:
This error may occur suddenly. When you power on your PC, It will show the windows logo. But it won’t bring any login screen. Instead of login screen, You will see the blue screen and messages something like –
"Windows has encountered a problem communicating with a device connected to your pc.This error can be caused by unplagging a removable storage device...,or by faulty hardware such as a hard drive or CD-ROM.Make sure any removable storage is properly connected and then restart your pc. File:\Boot\Bcd Status:0xc00000e9 Info an unexpected I/O error has occured."
Some users may not see any windows logo and they may see these messages in black screen. It completely indicates that it is a boot error.
What Causes this Problem:
Most of the time, This error occurs after inserting a bootable USB flash drive in PC. But, It has other reasons too. Any thirdparty software, viruses can cause this problem. Again, It can be a result of your hardware failure. All of these things make your necessary boot elements corrupted. That’s why windows can’t communicate with these files and shows the I/O error code: 0xc00000e9.
Sometimes, Hard disk problem is also responsible for it. If you have a very old hard disk, You have a good chance to face it. Again, It can be a result of BIOS misconfigurations.
How to Fix Error 0xc00000e9: Unexpected I/O Error Has Occurred
Well, If you want to resolve this problem, You will require some basic knowledge. These are not hard. I will explain very easily. Here are the methods you can follow.
Last Known Good Configuration:
The first thing you can do is choosing last known good configuration from advanced boot menu. To do it, Press and hold F8 button from keyboard after switching the power button on when the PC manufacture logo appears on screen. Then, You will see the legacy advanced boot menu. Choose last known good configuration by arrow buttons of keyboard. Then hit Enter. It is applicable for windows 7. But, If you are running windows 8/8.1 or 10, You will have to enable advanced boot menu manually. Then you can choose this option. To know how to do it, Read: Enable Legacy Advanced Boot Menu
You also should check, If you can boot into safe mode with command prompt or not. You can get the safe mode option in the advanced boot menu that i mentioned above. If you are a windows 10 or 8 user, You have to enable this menu manually. Anyway, You will need to run chkdsk /f C: command, If you can boot. Sometimes, It may fix unexpected I/O error.
Default BIOS Settings:
Sometimes, This problem “An Unexpected I/O Error Has Occurred” can be a result of incorrect BIOS settings. You can manually fix it very easily. To do it –
- Switch On the Power Button.
- When your monitor shows anything press F2. Different PCs may have different BIOS menu button. But F2 is the most common.
- When you are in BIOS menu, Press F9 to load default configuration.
- Now, Press F10 and then press Enter to save the settings and restart.
Sometimes, This method work. If it doesn’t help you, Please follow next one.
Acually, It is the best method to fix “Error 0xc00000e9: An Unexpected I/O Error Has Occurred“. In most cases, It should resolve the issue. To rebuild BCD, You will need windows bootable media. Then follow these things.
- Insert bootable USB flash drive or DVD in PC and restart.
- It may ask “Press any key to continue…”. Just press any button from keyboard.
- Now, Windows setup window will be appeared. Just click Next.
- Choose Repair your computer.
- Go to Troubleshoot > Advanced Options > Command Prompt.
- Now, In command box, Type Bootrec.exe and hit Enter.
- Again type, bootrec /RebuildBcd and press Enter.
You can learn more from here: https://support.microsoft.com/en-us/kb/927392
If you are lucky, It should fix the boot error. If it doesn’t work, You can follow next steps.
OK. This is the last basic method you can try. If none of the above methods work, You can do clean windows installation from a bootable media. I hope, This will fix your problem. If you don’t know how to bootable a USB flash drive, You can read this article: Create Bootable Pendrive
Check Hard Disk and Cable:
Sometimes, You may encounter problem during rebuilding BCD or reinstalling windows. It may not find any partition to do anything. In that case, There must be a problem with your hard disk drive or its cable. So, You can open CPU and check for the problems. You can try any extarnal hard disk to boot. If you see other external HDD are OK. You may consider buying or repairing your hard disk.
I hope, These information will help you to fix An Unexpected I/O Error Has Occurred. You may know any other solution that works. I will be happy, If you share it in comment box.