How to remove SunnyDay Ransomware and decrypt .SunnyDay files

What is SunnyDay Ransomware

SunnyDay is the name of a devastating ransomware infection. It was developed to cause encryption of personal data and help its developers capitalize on it. After restricting access to files using the .SunnyDay extension, the virus starts blackmailing victims into paying a fee for decryption. This information is presented inside of a text note (!-Recovery_Instructions-!.txt) created upon encrypting targetted data.

Victims are guided to contact developers using e-mail communication (restoreassistance_net@wholeness.business or restoreassistance_net@decorous.cyou) and pay for special decryption software. Cybercriminals warn that trying to use any third-party software to decrypt the data will result in the immediate damage of files. It is also stated that all encrypted files have been uploaded to servers of cybercriminals, which, in case of refusing to pay, will be forwarded (sold) to parties potentially interested in it. Additionally, victims are offered to send 2 or 3 non-important and get them decrypted for free. This is used by swindlers to show they are actually able to decrypt the data. Unfortunately, decrypting data without the help of cybercriminals is more likely to corrupt data and make it no longer decryptable. It is very possible that ransomware developers incorporated protection that detects any unauthorized attempts to modify data. Users can recover their data using a copy of files backed up on uninfected storage. Unfortunately, this does not abolish the threats of having collected data leaked to online resources. Business victims are always subject to reputational damage – this might be the biggest cost for getting infected with ransomware. Below, we explain how to delete SunnyDay Ransomware and try to recover your data for free in case no backups are at disposal. Note that removing the virus will not decrypt your data, but simply prevent it from running further encryption.

How SunnyDay Ransomware infected your computer

SunnyDay Ransomware does not have a single distribution method – it can be promoted through e-mail phishing letters, trojans, fake software installers/updates, unreliable downloads from P2P networks, and other suspicious vectors as well. E-mail spam is one of those channels to articulate from this list. Cybercriminals use this method to deliver malicious attachments or links and trick users into opening them. It can be MS Office documents, PDF, EXE, JavaScript, Archive, or any other files that seem innocent and legitimate to inexperienced users. Instead, they are intentionally modified by senders to contain and install malicious infections once opened. When it comes to targeting business organizations, ransomware developers may try to find some network vulnerabilities and exploit them to commit the attack. Sometimes it can be a NAS (Network Attached Storage) brute-forced by cybercriminals to infect connected computers.

1. Download SunnyDay Ransomware Removal Tool
2. Get decryption tool for .SunnyDay files
3. Recover encrypted files with Stellar Data Recovery Professional
4. Restore encrypted files with Windows Previous Versions
5. Restore files with Shadow Explorer
6. How to protect from threats like SunnyDay Ransomware

SunnyDay Ransomware files:


!-Recovery_Instructions-!.txt
{randomname}.exe


SunnyDay Ransomware registry keys:

no information

How to decrypt and restore .SunnyDay files

Use automated decryptors

Download Kaspersky RakhniDecryptor

Use following tool from Kaspersky called Rakhni Decryptor, that can decrypt .SunnyDay files. Download it here:

There is no purpose to pay the ransom because there is no guarantee you will receive the key, but you will put your bank credentials at risk.

Dr.Web Rescue Pack

Famous antivirus vendor Dr. Web provides free decryption service for the owners of its products: Dr.Web Security Space or Dr.Web Enterprise Security Suite. Other users can ask for help in the decryption of .SunnyDay files by uploading samples to Dr. Web Ransomware Decryption Service. Analyzing files will be performed free of charge and if files are decryptable, all you need to do is purchase a 2-year license of Dr.Web Security Space worth $120 or less. Otherwise, you don’t have to pay.

If you are infected with SunnyDay Ransomware and removed from your computer you can try to decrypt your files. Antivirus vendors and individuals create free decryptors for some crypto-lockers. To attempt to decrypt them manually you can do the following:

Use Stellar Data Recovery Professional to restore .SunnyDay files

1. Download Stellar Data Recovery Professional.
2. Click Recover Data button.
3. Select type of files you want to restore and click Next button.
4. Choose location where you would like to restore files from and click Scan button.
5. Preview found files, choose ones you will restore and click Recover.

Using Windows Previous Versions option:

1. Right-click on infected file and choose Properties.
2. Select Previous Versions tab.
3. Choose particular version of the file and click Copy.
4. To restore the selected file and replace the existing one, click on the Restore button.
5. In case there is no items in the list choose alternative method.

Using Shadow Explorer:

1. Download Shadow Explorer program.
2. Run it and you will see screen listing of all the drives and the dates that shadow copy was created.
3. Select the drive and date that you want to restore from.
4. Right-click on a folder name and select Export.
5. In case there are no other dates in the list, choose alternative method.

If you are using Dropbox:

1. Login to the DropBox website and go to the folder that contains encrypted files.
2. Right-click on the encrypted file and select Previous Versions.
3. Select the version of the file you wish to restore and click on the Restore button.

How to protect computer from viruses, like SunnyDay Ransomware, in future

1. Get special anti-ransomware software

Use ZoneAlarm Anti-Ransomware

ZoneAlarm Anti-Ransomware Dashboard

ZoneAlarm Anti-Ransomware Alert

ZoneAlarm Anti-Ransomware Blocked

Famous antivirus brand ZoneAlarm by Check Point released a comprehensive tool, that will help you with active anti-ransomware protection, as an additional shield to your current protection. The tool provides Zero-Day protection against ransomware and allows you to recover files. ZoneAlarm Anti-Ransomware is compatible with all other antiviruses, firewalls, and security software except ZoneAlarm Extreme (already shipped with ZoneAlarm Anti-Ransomware) or Check Point Endpoint products. The killer features of this application are: automatic file recovery, overwrite protection that instantly and automatically recovers any encrypted files, file protection that detects and blocks even unknown encryptors.

2. Back up your files

As an additional way to save your files, we recommend online backup. Local storage, such as hard drives, SSDs, flash drives, or remote network storage can be instantly infected by the virus once plugged in or connected to. SunnyDay Ransomware uses some techniques to exploit this. One of the best services and programs for easy automatic online backup is iDrive. It has the most profitable terms and a simple interface. You can read more about iDrive cloud backup and storage here.

3. Do not open spam e-mails and protect your mailbox

Malicious attachments to spam or phishing e-mails are the most popular method of ransomware distribution. Using spam filters and creating anti-spam rules is good practice. One of the world leaders in anti-spam protection is MailWasher Pro. It works with various desktop applications and provides a very high level of anti-spam protection.