Your app can protect its data from unauthorised acces by encrypting it with one of these components which implement a range of standard encryption and hashing algorithms. Including DES, TripleDes, RSA, Blowfish, Rijndael, RC2.
Solution Center - Code examples using Data Encryption Components
 I'm want my code to generate an MD5 hash of my file so that people can check it has not been modified
 I need my application to encrypt an entire file before I send it over the Intenet.

Delphi Data Encryption Components by LMD Innovative

LMD StoragePack 2.01

LMD StoragePack is a collection of 10 native VCL components that can be compiled into your application royalty free. StoragePack controls are used to save/restore application specific data. Possible target formats are the Windows Registry or XML files

Delphi Data Encryption Components by Bean Software

Crypt Component 1.1

Common Crypt Component is product intended to programmers of Win32, .NET, Classic ASP, ASP.NET and Mobile applications, who wants to protect sensitive data or even files with powerful password protection. It is small, fast, multiplatform, low cost, intuitive and extremely "easy to use" component. You don't need to loose your working time to code, test and debug cryptography. Crypt can do it for you on a fast and simply way, so you can concentrate to other specific parts of your projects.

Delphi Data Encryption Components by AidAim Software LLC

CryptoPressStream V1.0

CryptoPressStream is a streaming compression and ecnryption library. It provides transparent access to compressed or encrypted data stored in the stream object. All stream objects are 100% compatible with TStream and have some advanced functionality like progress event, LoadFromStream, LoadFromFile, SaveToStream, SaveToFile methods, Lock and Unlock methods for multi-thread usage.

Delphi Data Encryption Components by EldoS Corporation

SecureBlackbox V6.0.144

SecureBlackbox™ is a software component that adds support for MIME (including S/MIME and PGP/MIME), SSL/TLS, HTTPS, FTPS, SSH, SFTP, PGP, PDF standards to your application. SecureBlackbox primary goal is to provide basic technology for the wide range of applications, hiding the details of low-level protocols and algorithms, used by the parties during secure conversations.

Solid File System (SolFS) V3.2.0.100

Solid File System supports per-stream or whole-storage encryption of the files being stored.