System and method for file encrypting and decrypting

A processing method for file encrypting/decrypting to encrypt files or decrypt files during file access, comprising:

• connecting an external device to a host;
• when an agent module in the host verifies the identification information of the external device, loading, by an operation system in the host, an encryption partition;
• encrypting, by the agent module, a plaintext file in the encryption partition as an encrypted file;
• accessing the encrypted file from the encryption partition, by the agent module, decrypting the encrypted file and outputting the plaintext file;
• and
• when the host does not verify the identification information correctly, by the agent module, stopping verifying and detecting whether there is another external device connected to the host.

A processing method for file encrypting/decrypting, comprising:

• connecting an external device to a host;
• detecting the agent module in the host to verify the validity of the identification information of the external device;
• when the identification information is not valid or the external device does not connect to the host, by the agent module, prohibiting the encrypted files in the encrypted folder from being decrypted;
• when the identification information is valid, determining the access type for the encrypted folder;
• when the plaintext file is written into the encrypted folder, by the agent module, encrypting the plaintext file and outputting the encrypted file;
• and
• when the encrypted file is accessed from the encrypted file, by the agent module, decrypting the encrypted file and outputting the corresponding plaintext file.