MS Excel provides you with a wide range of features to keep and analyze the data seamlessly. You can perform computations, generate charts as well as define your custom logic using VBA modules. Knowing the importance of the data in spreadsheets, MS Excel allows you to protect the workbooks using encryption. Furthermore, you can password protect the Excel files to avoid unauthorized access. In accordance with that, this article covers how to encrypt/decrypt and password-protect Excel files using Java.