Restoring encrypted files, particularly those locked by ransomware, involves removing the malicious software and then using backups, specialized decryption tools, or cloud version history to recover data. Here are the main strategies for restoring encrypted files:
No More Ransom Project: If files are encrypted by ransomware, this initiative (supported by law enforcement and security firms) provides a database of known decryption keys and applications to help recover files without paying the ransom.
Cloud Backup Restoration (e.g., OneDrive): If you use cloud services like OneDrive, they often detect massive file changes (like ransomware) and allow you to restore your entire drive to a point in time before the attack. Users can also check the online recycle bin for unencrypted file versions.
Security Software Remediation: Programs like Bitdefender offer ransomware remediation features that create automatic backups of important files. When an attack is detected, this tool can restore files automatically without needing to pay the ransom.
Data Recovery Programs: In cases where files were deleted or overwritten during an encryption process, USB-based data recovery tools (like @ctive Boot Disk) can sometimes recover original, unencrypted versions of the files before they were completely overwritten.
EFS Certificates (Windows): If files were encrypted using Windows EFS, you must have the original EFS certificate to decrypt them, which may require accessing the user profile or using a Live Linux Distro to locate the certificate. Key Considerations:
Do Not Pay: Experts advise against paying ransoms, as it does not guarantee file recovery.
Act Fast: The more you use a computer after data is deleted or encrypted, the lower your chances of recovery as the data may be overwritten.