There are a variety of different ransomware variants that encrypt your data with no intention of ever decrypting it. There are also ransomware distributors who are happy to collect ransom payments but have no interest in returning anyone’s data.

Innocent victims often fall prey to ransomware hoaxes or find problems with ransomware decryptors. They all end up in the same place they started, without their valuable data.

Some of the groups behind the most prevalent ransomware viruses are working to build up confidence that victims will receive their data if they simply pay the ransom, but victims have learned the hard way that paying the ransom comes with no guarantee.

Purely destructive ransomware
There have been a number of ransomware viruses that infect systems only to delete victims’ files and then demand a ransom payment. One version—dubbed Ranscam because it is a ransomware scam—does exactly this. Similarly, AnonPop also pretends to be ransomware, deleting victim files rather than encrypting them.

The good news is that both Ranscam and AnonPop do not wipe the data from the disk. Wiping writes over data multiple times so that it cannot be recovered. That means if your files are deleted by Ranscam and Anonpop, you may be able to get them back using a file recovery program. Victims of Anonpop can also use their “system restore” feature to restore files and settings.

Ransomware hoaxes
Citrix did a study of 200 UK companies who had received fake ransom demands and found that 63% of them still paid the ransom. Why? Because they were unsure whether the demand was real or fake. Victims sometimes received demands for ransom in email, through browser popups, or in messages on their mobile devices.

Sometimes victims are unable to obtain decryption keys because ransomware authors stop supporting a particular version of a ransomware virus. But this doesn’t stop them from spreading those versions around and demanding ransom, even though there is no way to recover the data.

In some cases, new versions of ransomware are released because anti-malware researchers have released decryptors for a previous version. However, in other cases, ransomware authors upgrade their software proactively before a flaw has been discovered. For example, the creators of JIGSAW made updates to their code that changed encryption packages, but versions in the wild still contained the old code and could not be decrypted.

Occasionally, there are bugs in ransomware code that prevent extortionists from generating decryption keys. CryptXXX came out with a new version, but bugs in the payment system prevented it from sending decryption keys to victims who paid. Those who were infected were able to pay the ransom, but the decryption capability no longer existed or was unavailable.

Cybercrime power struggles
Some victims of ransomware have started communicating with an extortionist or even paid a ransom demand and then found that the extortionist was apprehended by law enforcement. Law enforcement forensically preserves data and evidence for court and shuts down services, but victims are left without decryption keys, so their machines wipe data or remain encrypted. At some point it is possible that they will receive their money back, but not their data.

Other extortionists have been taken down by a rival cybercrime groups or hackers in the midst of their negotiations with victims, and in some cases, victims have already paid the ransom or some portion of it. Unfortunately for these victims, their transactions were lost in the limbo of cybercrime power struggles, and they may not end up getting their data back.

The big cybercrime groups behind some of the major ransomware variants out there try to establish some level of integrity with their victims so that they will pay the ransom. But there are plenty of others who show that trusting a criminal is a gamble at best.

Don’t gamble with your data. Paying ransoms is not an effective way to recover data. Ensure that you have a robust backup and recovery strategy in place and you’ll never have to pay the ransom.

This article originally appeared on Carbonite.