There two ways to tell:
1. Start Best Folder Encryptor, select one encryption type at the bottom-left cornor in the software window and encrypted folders of this type will appear in the list.
2. A Flash-encrypted folder becomes a 1 KB shortcut after encryption which distinguish itself from others. Open a Full-encrypted folder doesn't need the password, but each file inside does. A Diamond-encrypted folder is of the same size as before, and needs the password to open.
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