A ransomware victim is under pressure, which makes misleading download pages especially risky. Use this checklist before running any file labeled StopDecrypter, universal decryptor or ransomware recovery tool.
1. Match the download to the claimed software
Check the publisher and destination. If the link points to a project with a different name or purpose, do not treat it as the requested decryptor.
2. Prefer the current official source
The legacy StopDecrypter utility was replaced. A current vendor page with documented limitations is safer than an old mirrored executable.
3. Scan the file and preserve evidence
Use your security tools to scan the download, and keep the original encrypted files on separate storage.
Do not confuse a warning with a false positive automatically
Security tools can flag specialized utilities, but that does not mean every warning should be ignored. Verify the publisher and hash or signature information provided by the vendor.
4. Contain ransomware first
If the malware is still active, decryption can be undone by re-encryption. Recovery starts with containment.
5. Accept technical limits
No legitimate STOP/Djvu decryptor guarantees success for every victim. If a key is unavailable, archive the encrypted files rather than deleting them.
Then follow the preparation workflow.