an operating system wasn't found

Symptoms

Press Ctrl+Alt+Del to lớn restart

Resolution

1. Boot from any DVD or USB Windows 7, 8, or 10 truyền thông media.

2. Once you have reached the Windows Setup screen (where you select the Language, Time and Keyboard settings), press the SHIFT + F10 keys to lớn bring up the Command Prompt.

Step 2: Find out whether your disk is mix to lớn GUID Partition Table (GPT) or Master Boot Record (MBR):

1. Within the Command Prompt window, type the following commands, pressing Enter after each command:

   diskpart

   list disk

2. Look for your disk and see if the GPT column has an asterisk (*) – this will indicate the disk is GPT. If no asterisk is found, then the disk is mix as MBR.

3. Type exit and press Enter.

Step 3a: If the type is MBR:
 

1. From the Command Prompt, type the following command and press Enter: 

   dir a:

   1. If drive A: is found and a directory is displayed, kiểm tra for the \Windows thư mục in the directory. If it is there, that is the System Drive. Skip to lớn step 2.

   2. If drive A: is not found or it doesn’t contain the \Windows thư mục, type the following command and press Enter:  

      dir b:

   3. Continue through the alphabet until the drive with the \Windows thư mục is found, but skip the X: drive. That will be the install files from the USB or DVD you are using. The most common location is the C: drive, ví that example will be used in the rest of the article.

2. Once it is found, type the following command:

   bcdboot C:\Windows /S C:

   1. In this case, C is the drive where the \Windows thư mục was found. If the Windows thư mục is on a different drive, use that drive letter instead of “C” in the bcdboot command above.

3. The message, Boot files successfully created, must be shown before you can continue.

4. Type the following commands, pressing Enter after each command: 

   diskpart

   list disk

   sel disk C

   1. In this case, C is the drive where the \Windows thư mục was found. If the \Windows thư mục is on a different drive, use that drive letter instead of “C” in the sel disk command above.

5. Type the following commands, pressing Enter after each command: 

   list vol

   sel vol C

   1. In this case, C is the drive where the \Windows thư mục was found. If the \Windows thư mục is on a different drive, use that drive letter instead of “C” in the sel vol command above.

      Xem thêm:

6. Type the following command and press Enter:

   active

   1. You should get a confirmation that the volume has been successfully mix as active. If you don’t get the confirmation, it means that either the disk is mix to lớn GPT (not MBR), or there is a problem with the disk. Make sure you are working with the right disk.

7. Type the following command and press Enter:

   exit

8. Reboot the device. You can vì thế this quickly from the command prompt by typing the following command and pressing Enter: 

   shutdown -f -r -t 00

Step 3b: If the type is GPT:

1. From the Command Prompt, type the following command and press Enter:

   dir a:

   1. If drive A: is found and a directory is displayed, kiểm tra for the \Windows thư mục in the directory. If it is there, that is the System Drive. Skip to lớn step 2.

   2. If drive A: is not found or it doesn’t contain the \Windows thư mục, type the following command and press Enter:  

      dir b:

   3. Continue through the alphabet until the drive with the \Windows thư mục is found, but skip the X: drive. That will be the install files from the USB or DVD you are using. The most common location is the C: drive, ví that example will be used in the rest of the article.

2. Type the following commands, pressing Enter after each command: 

   diskpart

   list disk

   sel disk C

   1. In this case, C is the drive where the \Windows thư mục was found. If the \Windows thư mục is on a different drive, use that drive letter instead of “C” in the sel disk command above.

3. Type the following command and press Enter:

   list part

4. Look for the partition labeled as System.

5. Once it is found, assign the letter R to lớn the partition. If the letter R is already taken, you can choose any unassigned letter. To assign the letter, type the following commands and press Enter after each command:

   assign letter=r:

   exit

6. Return to lớn the Command Prompt, type the following commands one line at a time, pressing Enter after each line:

   cd /d r:\EFI\Microsoft\Boot\

   ren BCD BCD.bak

   bcdboot c:\Windows /l en-us /s m: /f UEFI

   Note: In the last command, /l en-us sets the Windows language to lớn English. To mix a different language, replace en-us with a different language code (such as de-de for German).

7. Reboot the device. You can vì thế this quickly from the command prompt by typing the following command and pressing Enter: 

   Xem thêm: còn mấy ngày nữa tới trung thu

   shutdown -f -r -t 00