In the last day, visitors to TrueCrypt’s website have been redirected to a page with an announcement that development for the encryption software has ended. The site now shows a warning message that TrueCrypt is not secure, providing directions for users to migrate data to alternative systems.

Many security-minded computer users have been ardent supporters of TrueCrypt, which has shipped with most versions of Microsoft’s Windows operating system since Vista, according to Krebs On Security. The anonymous developers behind the software said they decided to retire TrueCrypt after Microsoft ended support for Windows XP last month. (It’s the same reason China cited when it issued a ban on Windows 8 on government computers.) An updated version of TrueCrypt removed encryption functionality, but users could still decrypt data. The key to sign the installer file matches an older signature, suggesting the message is genuine.

Still, this redirected webpage has spawned its share of conspiracy theories about the U.S. government’s role in TrueCrypt’s demise. Some peole are also hoping volunteers can keep TrueCrypt running.