Work With Files

We focus on designing Boxcryptor as user-friendly and easy to use as possible. Once Boxcryptor is set up, you will not notice that your files are encrypted. Just keep working with your files as usual.

On-the-fly Encryption

Boxcryptor encrypts your data on-the-fly and it encrypts every file separately. When you work with your files there is no need for bulk decryption. You can just open any encrypted file and it's content will be decrypted automatically in the background. When you save your changes, the contents are encrypted automatically again. Simply work with your protected data with Boxcryptor without noticing the cryptographic process behind it.

2-1   Help On-the-fly Detailed

We accomplish this simplicity by creating a virtual drive on your machine. It acts like an encryption-empowered window to your data. All your files – whether they are encrypted or not – can be accessed via this virtual Boxcryptor drive.

Encryption and Permission Hierarchy

You can decide for every file or folder which security level you want to set. Boxcryptor gives you full control over this. You can allow others to access a file by giving permissions, you can choose if the filename should be encrypted as well, or you can leave single files and folders unencrypted.

To make things easier all properties of a file are inherited hierarchically from its containing folder. For example, if you have an encrypted folder called My Secret Files and add a file to this, the file will be encrypted automatically and the chosen permissions will be inherited. The same applies to whole folders.

2-1 Help Inheritance

inline-no-border   Permission A Encrypted and permission to access for Alice

inline-no-border   Permission B Encrypted and permission to access for Bob

inline-no-border   Permission AB Encrypted and permission to access for Alice and Bob

Note: If you add a file to a folder that is not encrypted, Boxcryptor will ask you if you want to encrypt it or not.

Work With Your Files

With Boxcryptor, you never need to manually decrypt any data when you want to work with it.

Boxcryptor deeply integrates into Windows by creating a virtual drive. The encryption takes place on-the-fly. Therefore, all other programs, including the Windows Explorer, will work the same way as with files on your hard drive.

To work with your encrypted files, just browse to the Boxcryptor Drive in Windows Explorer and edit, view, copy, or move files as in any other folder.

If you do not have Boxcryptor permissions to open a file, some programs will show errors like "Invalid parameter" or "cannot open". In such a case, verify that you have the permission to open the file via right-clicking the file or folder → Boxcryptor → Manage Permissions. See Share with Boxcryptor users for more info.

How to Recognize Encrypted Files

Boxcryptor allows you to have encrypted and unencrypted files and folders. Encrypted files and folders in the Boxcryptor drive are marked with small icons that indicate their current state.

inline-no-border   Help Windows Overlay Encrypted Synced encrypted and synchronized

inline-no-border   Help Windows Overlay Encrypted Syncing encrypted and synchronization in progress

Dropbox Smart Sync online-only files will appear slightly greyed-out in the Boxcryptor drive. See On-Demand Files for more info.

Encrypt Existing Files and Folders

If you already have files stored in your cloud, you can encrypt your existing files as well. This is how it works:

  • Browse to the file or folder you want to encrypt.
  • Right-click the selection and chose Boxcryptor → Encrypt in the context menu.
  • Wait for your cloud provider’s sync client to sync everything.

Please wait until your cloud provider’s client synchronized your files to the cloud, before you start working with them. This helps to prevent sync conflicts.

Note: To improve synchronization results, Boxcryptor adds an _encrypted suffix to the names of the files and folders you encrypt. After synchronization is completed, you can rename them.

Work With Filename Encryption

Filename encryption effectively prevents outsiders from analyzing your data structure. However, it also comes with the cost of a slightly slower performance and higher efforts regarding a proper setup. If you want to use filename encryption with shared files and folders, please read our blogpost, especially chapter 5, before proceeding.

A filename encrypted file will look like this: 怐悰挦抱沯抮殥枏曕擟敯漢怏搬濂檬浉楻挭抧柜欅䀣.bc

Filename encryption can be enabled globally. All new encrypted items that do not inherit encryption settings from their parent folders will be encrypted with filename encryption. Existing encrypted files, however, will not be touched, which means that you have to activate filename encryption for existing files manually. Filename encryption is one of the properties that files inherit from their parent folder. Therefore, if you save a file to a folder with filename encryption, it will have filename encryption as well.

Conclusively, even if filename encryption is enabled globally, new files that are created in a folder without filename encryption will also have no filename encryption due to the encryption property inheritance.

To activate filename encryption globally, go to Boxcryptor Settings → Security → Encryption and check Enable filename encryption.

To change the filename encryption settings of already encrypted items, right-click them and select Boxcryptor → Enable / Disable filename encryption in the context menu. Follow the instructions and make sure to let the files sync completely before you continue to work with them.

How to Decrypt Files

You do not need to decrypt your files when working with Boxcryptor.

If there is a scenario in which you want to decrypt a file, here are some possibilities:

  • If you want the decrypted files synced to your cloud provider, the easiest way is to right-click on the file or folder you want to decrypt and select Boxcryptor → Decrypt.
  • If you want to copy or move your files to another location in decrypted mode, just select the files in the Boxcryptor drive with the Windows Explorer and copy or move them to the new location. The data will be decrypted automatically.

On-Demand Files

Some cloud providers offer that not all files are automatically synced to your device. Instead, only the directory structure is replicated on your device and files are downloaded on demand when you open them. This saves valuable disk space and bandwidth while still being able to access every file from your computer.

Dropbox Smart Sync

Dropbox Smart Sync defines three states for files and folders:

  • Online-only content shows in your local Dropbox folder, but doesn’t use the full amount of space that the file would. In your file explorer, you can see the file, but the content isn’t fully downloaded until you need it. Only information about the file, such as the file name, location, and date the file was updated, is downloaded.
  • Mixed state folders contain both local and online-only content.
  • Local content is downloaded and saved on the hard drive of your computer. You can directly edit these files from applications on your computer.

Boxcryptor preserves the Smart Sync state of files in Dropbox, downloads files via Dropbox on demand when another application opens an online-only file and displays the Smart Sync state in the Boxcryptor drive.

The Smart Sync state of files is indicated by the file icon. The file icons of online-only files are faded or "grayed / whited" out.

Note: The Dropbox Smart Sync state of folders is not shown in the Boxcryptor drive. If you want to determine the Smart Sync state of a folder, right-click it and choose Boxcryptor → Show Original in Dropbox. You can then identify the Smart Sync state using the Dropbox icon overlays as explained here.

Opening online-only files

You can browse to an online-only file in the Boxcryptor drive and directly open it. Boxcryptor will immediately trigger a download via Dropbox Smart Sync and waits until it finished. After the download finished, the file open process will continue. If the download takes more than 3 seconds, Boxcryptor will abort the file open operation in order to preserve the responsibility of the Boxcryptor drive. You can track the download progress in the Dropbox system tray menu and once the download has finished, you can re-try to open the file.

Downloading online-only files

If you want to make an online-only file locally available without having to open it, you can right-click any online-only file and choose Boxcryptor → Download. Please note, that it is currently not possible to revert this operation, i.e. make a locally available file online-only. If you'd like to perform this action, please perform it using the Dropbox application. You can select the original item directly in the Dropbox folder by right-clicking it and choosing Boxcryptor → Show Original in Dropbox.

Can I manage permissions of online-only folders?

Permissions are persisted in a file named FolderKey.bch within a folder. When this file is online-only, it will be automatically downloaded by Dropbox when opening the Manage Permission dialog in Boxcryptor. If the file cannot be downloaded because there is no internet connection, permissions cannot be changed at that time. In this case, go online and try it again.

Why can opening an Office application (Word, Excel, Powerpoint) be very slow?

When you open an Office application, it tries to read all recently opened files. If these files are online-only, Dropbox downloads them and blocks the opening application until the download has finished. Clearing your recently opened files list in the Office application resolves this issue.

Why are certain files always local even after I made them online-only?

Please see the the question above. When a file is included in the recently opened file list of an Office application, opening the application will always cause Dropbox to download them. Clearing your recently opened files list in the Office application resolves this issue.

When do I need an internet connection while working with Smart Sync enabled?

You need an internet connection when trying to open an online-only file or working in an encrypted folder whose folder key file (FolderKey.bch) is online-only. We recommend to always make an encrypted folder completely locally or online-only available and avoid having mixed state folders when you anticipate a bad internet connection.

Can I download a folder in the Boxcryptor drive?

Yes! To do this, click on Boxcryptor → Download in the context menu of the folder. This will download all files recursively. Note that this will only download the current state, files added remotely in the future will not be automatically downloaded.

Can I make a file or folder online-only in the Boxcryptor drive?

No, it is currently not possible to make a file or folder online-only when you are in the Boxcryptor drive. If you want to make a file or folder online-only, you must go directly to the Dropbox folder and choose Smart Sync → Online Only in the Dropbox context menu. To identify a file or folder in the Dropbox folder, you can right-click the item in the Boxcryptor drive and choose Boxcryptor → Show Original in Dropbox.

Can I use Windows Search to find online-only files?

You can find online-only files by name, but it is not possible to find them by their content because online-only files do not contain any content.

OneDrive Files On-Demand

OneDrive Files On-Demand is officially supported by Boxcryptor, since the new official release of the Windows 10 Fall Creators Update.

Google Drive File Stream

Google Drive File Stream is officially supported by Boxcryptor on all platforms. Find more information on our blog.

Box Drive

Box Drive is also officially supported by Boxcryptor.