Do you have some BitLocker alternative recommendations?

TrueCrypt

TrueCrypt is a full disk encryption program that works on Windows Vista/XP, Mac OS X, and Linux. It owns the following features:

Mounts a virtual encrypted disk created inside a file as if it were an actual disk.

With the pre-boot authentication, TrueCrypt can encrypt the startup partition in Windows.

Automatic, real-time (on-the-fly), and transparent encryption.

VeraCrypt

Based on TrueCrypt, IDRIX designed VeraCrypt as a free disk encryption program. It strengthens the encryption algorithms used for systems and partitions, making them resistant to advanced brute-force attacks.

Offers both GUI & command line for different users.

Highly portable that can encrypt a USB stick or similar with no prior installation.

Strong encryption as well as multiple encryption methods.

AES Crypt

By encrypting files using the Advanced Encryption Standard, AES Crypt is a sophisticated file encryption tool that works with the Windows shell or runs with the Linux command prompt (AES).

Your most sensitive files can be securely encrypted with AES Crypt using a strong 256-bit encryption algorithm. Similar to the BitLocker recovery key, an encrypted file is absolutely useless without a password. You don't have to worry about that someone will read your critical information after it has been encrypted.

Encrypto

Encrypto utilizes AES-256 encryption to safeguard files. Files can be encrypted with Encrypto before being sent to friends or coworkers. Send a file with more protection by dropping it into Encrypto, setting a password, and sending it. Although it's a commercial program, it's still one of the best BitLocker alternatives.