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What is File Lock?
File Lock is a security web application that allows users to encrypt files. File Lock uses AES-256, which is an industry standard method of encrypting data - even used by the US Government. Keep in mind that longer passwords offer better protection.
File Lock can be used to encrypt files by any device that has a recent web browser. If your browser supports Web Workers (a message will be displayed if it doesn't), then not only will the browser not freeze during encryption, but it will act as a multithreaded application. This means your processor's extra cores will be used, even though web browsers usually can use only one.
Why do files I encrypt show up as unencrypted/Why doesn't my file open properly after decryption?
When you encrypt files, their names get ".enc" added to them, to show that they are encrypted. You may have renamed the files or saved the files with an unusable name.
To fix this problem, just rename the files to the proper name, such as "ImageOfFunnyCat.jpg" for a file that is not encrypted or "ImageOfFunnyCat.jpg.enc" for an encrypted one.
If you're having problems doing this, make sure your file manager lets you see file extensions.
What if I forget my password?
Unlike when you password protect a user account, there's no "forgot password" button with encryption. It cannot be undone without the password (or a successful attack, but no meaningful ones exist for AES).
See "What Is Encryption".
Why is my browser not compatible?
In short: it is not supported because there is no reasonable way to access the files you want encrypted.