As we have already learned, if the computer no longer works or if there were obvious problems, Windows 7 and Windows 10 allow you to recover the entire hard disk thanks to the system images. One thing that can not be done is the recovery of specific files, when errors of missing files that result from the effects of a virus, from badly programmed software, or from clumsy manual operations are reported. Thanks, in fact, to the internal backup functionality, on Windows 7 and Windows 10 you can easily set the creation of recovery points and disk cloning on another hard disk, internal or external.
If the pc has anomalies or errors, just restore the state of the computer a few days before, when the pc was fine.
To recover specific system files (for example dll files), without having to reinstall Windows entirely, instead you have to work in a different way and you can use two methods:
1) Using the Windows installation CD for Windows files only.
2) Through the system image created from a previous backup to recover lost files, deleted by mistake.
First of all I cannot fail to warn anyone who is preparing to replace or restore a missing Windows file that this is always a risky operation that can even worsen the situation. It is therefore advisable to operate only after having already made a full backup of the computer and if you are willing to reinstall everything from scratch if something does not work (see how to save everything before formatting and reinstalling Windows).
1) Retrieve the Windows 7 or Windows 10 installation disc or a recovery disc provided by the computer manufacturer (especially for laptops).
If it has been lost, you can download the Windows 7 installation DVD from the internet or use the Media Creation Tool to download the Windows 10 disc.
After inserting the disc in the DVD player or after copying the installation files on a USB stick (also using a program such as Rufus to burn ISO to USB) or mounted the ISO image of the system (see how to mount the ISO files), two types of procedure can be used.
If you want to use the automatic procedure, in another article read the guide to solving the error File not found if Windows does not work . SFC is the internal Windows tool that automatically restores corrupt or missing files from the installation disk, without having to make this copy manually.
If you prefer the manual procedure, you need to look for a file called Install.wim on the Windows 10 or 7 installation disk.
This file, Install.wim, is also found in the Windows AIK, the tool downloadable from the Microsoft website to create a customized installation CD for Windows 7.
To open the install.wim file, you need to use another software, 7Zip, capable of opening any type of archive.
NOTE for Windows 10 : If you download Windows 10 from the Media Creation Tool, after creating the USB stick with the installation files, you will find a file inside the Sources folder called install.esd . You can then convert the install.esd file to the install.wim file in the following way:
- Create a temp folder inside C
- Open the command prompt as an administrator and run this command:
dism / export-image /SourceImageFile:"D:\sources\install.esd "/ SourceIndex: 1 /DestinationImageFile:C:\temp\install.wim / Compress: max / CheckIntegrity
Remember to change the folder paths if they are different.
Eventually, inside C: / Temp, you will find the install.wim file.
If in the Install.wim archive, opened with 7Zip, there were multiple folders, it means that there are various versions of Windows inside.
To find the correct one, you need to copy the corresponding .xml file to the desktop, open it with the notepad and locate the word EditionID inside which says which version of Windows that folder corresponds to.
Now, after opening the folder corresponding to your operating system, you can search for the missing system files that are usually found in the C: \ Windows \ System32 or C: \ Windows \ SysWOW64 folders for 64-bit systems.
At this point, you can replace and restore the missing files .
If replacement is not possible because the files are in use, you must start your computer using a Linux distribution for a USB stick and copy the files from there.
2) If the lost files cannot be found on the installation disk, you can try to restore the files from a Windows system image created from a previous backup .
In this case, opening the hard disk where backups are made, you should find a folder called WindowsImageBackup .
By opening the various subfolders you should get to see a series of xml files and a very large VHD file (if there is another smaller one, it is not to be considered). That's the backup image that can be opened via the usual 7Zip .
Alternatively, you can mount the VHD file on a virtual hard disk:
Right click on " My Computer " and go to " Management ".
By opening disk management, press on the Action key at the top, then on " Link VHD file " and choose the VHD file which is located in the backup folder.
Now a new virtual hard disk should appear in computer resources which contains all the files inside the VHD file which, in this case, is the backup image, clone of the C disk of your Windows installation.
From here you can recover all documents, photos, videos and system files .
After finishing, you can disconnect the VHD and remove the virtual hard disk by going to Disk Management, pressing the right button on the Disk with the backup files, in the lower part of the window, where the hard disks are numbered.
Make sure not to check the box asking if you want to delete the VHD file.
To mount a VHD file you can also use the VHD Attach program which does everything automatically.
If problems persist, you can restore your computer to factory settings or you can use boot cd
