###### tags: `作業メモ` # How to Fix on Windows About how to repair Windows boot problems due to `SSD clone`, `Fail Windows Update` etc. This is a common problem when cloning slow 1TB hard drive data to 256GB SSD. Boot your PC after cloning to SSD, it's displayed an error message about `Operating System Not Found` or `No bootable device -- insert boot disk and press any key`. .....or it just shows `_` on a blank screen. Next, You have to make recovery drive like [this introduction](https://support.microsoft.com/en-us/windows/create-a-recovery-drive-abb4691b-5324-6d4a-8766-73fab304c246#WindowsVersion=Windows_10) and open `cmd.exe`. ## Boot Area Repair ### 1. Scan bootable operating system ```shell $ bootrec /scanos ``` ### 2. Rebuild BCD ```shell $ bootrec /RebuildBcd ``` ### 3. Fix Master Boot Record(MBR) ```shell $ bootrec /fixmbr ``` ### 4. Boot area recovery ```shell $ bootrec /fixboot ``` >`bootrec /fixboot` is a command that can fix the problem that Windows does not start due to the corruption of the boot area. ## `bootrec /fixboot` says" Access is denied " In Japanese, says `アクセスが拒否されました`. ### Check Disk in Boot area #### 1. Find the unlabeled drive. ```shell $ diskpart diskpart> list volume ``` #### 2. Select Volume of unlabeled drive. ```shell diskpart> select volume X ``` > X is 1,2,3...... #### 3. Label the Drive. ```shell diskpart> assign letter b: diskpart> exit ``` #### 4. Run `chkdsk`. ```shell $ chkdsk b: /r ``` ### Rebuild BCD Forcibly #### Format EFI partition (option) ```shell $ format b: /FS:FAT32 ``` <!-- BCDの修復 ```shell $ bcdedit /export c:\bcdbackup(元のBCDストアをバックアップする) $ attrib c:\boot\bcd -h -r -s(BCDファイルの隠し属性、読み取り専用属性、およびシステム属性を解除する) $ ren c:\boot\bcd bcd.old(BCDストアの名前を変更する) $ bootrec /rebuildbcd ``` --> #### Rebuild BCD command ```shell $ cd /d b: $ bootrec /Rebuildbcd $ bootrec /fixboot $ bcdboot c:\Windows /l ja-JP /s b: /f ALL $ exit ``` > Paths like `c:\Windows` vary depending on your environment. ### Tricks 🎉 `chkdsk` can run GUI. ```shell $ notepad ``` 1. Open `notepad` to use above command. 2. Click `File` 3. Click `Open` 4. It appers `Explorer Window`, then Right click `System Drive` 5. Click `Property`, then you can execute `Check Disk`