FAQ & Troubleshooting

I Cannot Install Boxcryptor

If the installation of Boxcryptor is not working, try the following:

Option 1:

Option 2: If this does not work, try starting the setup file manually with right-click → run as Administrator.

Option 3: If this does not help either, we need more feedback from the installer routine:

  • Press the Windows Key+R, type cmd and press Enter.
  • In the appearing window, type cd <path to your installation file>.
  • Now enter <installation file> /log log.txt.

This command generates a log.txt file in the same folder as your installation file, containing important information about the failed installation. Look it through to find the reason for the failed installation, or send it to us.

My Screen Goes Black on Install

During installation we need to stop the Explorer to install the kernel driver explorer integration. Sometimes the Microsoft Software Installer (msi) fails to restore previous applications. In this case, you need to manually restart the Explorer.

  • Open the Task manager (Ctrl+Shift+Esc).
  • Click on File → New task.
  • Type in "explorer" and hit enter to restore the explorer process.

I Cannot Update or Uninstall Boxcryptor

Sometimes deinstallation or an update of Boxcryptor fails with a request for the original installation file. This problem is caused by aggressive system enhancement apps.

To fix this, just download the installer for your currently installed Boxcryptor version from our changelog and provide it on request.

If this does not suffice, try Microsoft's deinstallation tool.

Boxcryptor is Using a Lot of CPU

CPU usage is completely dependent on the activity within the Boxcryptor drive. When many operations are executed within the Boxcryptor drive – such as reading and writing files – CPU usage will rise. When there is no activity in the Boxcryptor drive, there should not be any CPU usage.

However, it is possible that those activities are kind of invisible, for example when apps are running operations in the background, without the user’s interaction. A classic example for that is the indexing service of Windows.

Boxcryptor is Slow

An App is Slower Than Usual When Used With Boxcryptor

When an app is slower than usual when used in combination with Boxcryptor, the app might have a problem with handling Boxcryptor’s encryption. Boxcryptor simply acts as a filter, taking read and write requests from the operating system, and encrypting them on the way.

Well written apps write their files in blocks. In this case, Boxcryptor only needs to be active a few times during encryption and performance is not affected. Some apps, however, write each byte one by one. This results in many calls to Boxcryptor and leads to slower performance.

If you have trouble with one of your regular apps and performance is your priority, you could try out an alternative, to check if it can deal with Boxcryptor’s encryption better.

A Background Process is Causing High Load

Slow performance of the Boxcryptor drive might be caused by a background process performing a huge amount of file operations on the Boxcryptor drive without the user noticing. As Boxcryptor is then busy handling all the file operations of the background process, Boxcryptor has less time to handle file operations of other application and thus might feel slow. A classic example for a background service causing high load on the Boxcryptor drive is a search indexing service, e.g. Windows Search.

Icons or the Context Menu are Not Shown

Boxcryptor uses its own channel to communicate with Explorer to display overlay icons or the context menu. If neither is displayed, this communication might not work correctly. There are three possible reasons for this:

You have started either Boxcryptor or the Explorer as another user

Correct this by opening the Task Manager (Strg + Shift + Esc), first selecting BoxcryptorRestart and then ExplorerRestart.

There are too many Explorer processes running at the same time

Boxcryptor handles only a limited number of explorer processes simultaneously. Correct this by closing some Explorer instances via Task Manager (Strg + Shift + Esc).

All available spaces for the overlay symbols are occupied

Windows 10 has limited these to 9 free slots, so now all installed programs are fighting for them. Please take into account that every single symbol needs a free space.

The solution is to delete all unused entries:

  1. Open the registry: Windows key + R → enter regedit → press ENTER
  2. Navigate to this key: HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Explorer\ShellIconOverlayIdentifiers
  3. Delete any keys that you think are no longer needed or that resemble "SkyDrive". (SkyDrive is the old OneDrive.)
  4. Restart your system.

You are welcome to help alert Microsoft to this problem. Vote on it here via the Microsoft Feedback Hub.

How to Create a Debug Log

What is a Debug Log?

A debug log captures all internal events while Boxcryptor is running. It can help us to track down issues with Boxcryptor, for example bugs and incompatibilities with other software.

Does a Debug Log Contain Sensitive Data?

When you create a debug log, sensitive user information - like password, encryption keys, or actual file content will not be logged.

Which Information Does a Debug Log Contain?

The debug log captures the following information.

  • User interaction such as button clicks and in-app navigation
  • File operations (including unencrypted filenames)
  • Current Boxcryptor settings
  • Communication with our servers and your cloud provider(s)
  • System information such as OS version or required frameworks
  • Running programs
  • Boxcryptor related windows event log reports
  • User interaction and screenshots recorded with Windows Steps Recorder

How Do I Create a Debug Log?

  1. Go to your Boxcryptor installation folder (C:\Program Files (x86)\Boxcryptor), → double-click Boxcryptor (Debug).
  2. Reproduce all steps that lead to the unexpected behavior.
  3. Quit Boxcryptor by right-clicking on the tray icon → Exit.

A debug log archive (Boxcryptor-<Timestamp>.seclog.zip) is generated and saved to your desktop.

Additional System Information

If your system configuration matters, you can export information about it as follows:

  1. Press Windows → write msinfo32 → press Enter. The system information overview opens.
  2. Now go to FileSave to export the information and send it to us, in addition.

On-the-fly logging

If you run into a problem and want to create a log straight away, you can tell Boxcryptor to start logging while it is already running:

  1. Press Windows Key+R → type bc.cmd → press Enter. This opens an interactive Boxcryptor console.
  2. Enter debug → press Enter.
  3. Repeat the steps that lead to the problem.
  4. Quit Boxcryptor by right-clicking on the tray icon → Exit or disable logging via the console: debug --set-debug-mode=FALSE.

Logging Boxcryptor during Windows Startup

  1. Press Windows Key+R → type bc.cmd → press Enter. This opens an interactive Boxcryptor console.
  2. Enter debug --persistent → press Enter to enable persistent logging.
  3. Close the console window afterwards.

Boxcryptor will then notify you to disable it during startup.

Log filesystem accesses before execution

In rare cases it can be of interest to log accesses to the Boxcryptor drive before the file operation is carried out:

  1. Press Windows Key+R → type bc.cmd → press Enter. This opens an interactive Boxcryptor console.
  2. Enter debug --eager-logging → press Enter to enable persistent logging.
  3. Close the console window afterwards.

Windows Steps Recorder

To better understand how the issue was produced, we use Microsoft's integrated Steps Recorder tool to take screenshots, record mouse clicks and track keyboard input.

You will feel a slightly degraded performance while the steps recorder is running.

Microsoft's Step Recorder will not record any of your keyboard input (it only marks an action as keyboard input). As long as you write your passwords in password fields (that obfuscate inputs), the screenshots won't show them.

To make sure everything was recorded to your wishes you can open and check the Steps recording (Boxcrytor-<Timestamp>.seclog.zip\<Timestamp>-steps-recorder.zip\Recording_<Timestamp>.mht) before sending the log to us.

Disable Steps Recorder

If you do not want to have any user interaction recorded, you can either delete the Steps recorder log from the output .zip file or start the debug mode without screen recording, with these steps:

  1. Press Windows Key+R → type bc.cmd → press Enter. This opens an interactive Boxcryptor console.
  2. Enter debug --disable-steps-recorder → press Enter.
  3. Close the console window afterwards.

What Should I Do With my Debug Information?

Use our Boxcryptor help formular to send us the files with a detailed description of the problem or write to our support team, with the attached debug information.

Boxcryptor Crashes at Start

If Boxcryptor crashes when you start the software, it is likely that some component of the installation is at fault. To fix this, try the following steps:

  • Uninstall Boxcryptor.
  • Install the .NET-repairtool and follow its instructions.
  • Install the latest .NET framework.
  • Restart your system.
  • Install Boxcryptor again.

Problems with Windows 10 1809 (October Update)

Windows 10 1809 introduced a series of security features that may prevent Boxcryptor from functioning:

Boxcryptor uses Chromium Embedded Framework for web authentication, depending on the Device Guard or Code Integrity Policy it is possible that parts of the library are being blocked.

This issue has been fixed by Microsoft. Please make sure to have KB4487044 installed. To do so, press Windows Key + R → enter winver -> press ENTER and confirm that the displayed build number is greater than equal to 17763.316.

Problems on Windows 7

Boxcryptor requires some components that may be missing when automatic Windows Updates are disabled.

Please turn on automatic Windows Updates (recommended) or download and install KB2999226 manually.

More information about this update can be found here.

I Cannot Connect to the Boxcryptor Servers

Depending on your system or network configuration, Boxcryptor may not always be able to communicate with our servers. However, there are some workarounds for the following scenarios.

After the signing in, the App just returns to the sign-in screen

This may happen due to malconfigured SSL / TLS settings. Boxcryptor requires TLS 1.2 or greater for a secure client-server communication. On Windows 7 or some misconfigured computers, TLS 1.2 may not be enabled. Have a look at this Microsoft documentation to learn how to enable TLS 1.2. The most convenient way to solve the issue is the documentation attached Easy Fix Installer.

We have seen incidences where some critial .NET updates where not installed on Windows 7 computers which are most likely causing connectivity issues even with enabled TLS 1.2 support. Microsoft offers some troubleshooting tips on each update, check out their respective landing pages.

Warning: This is no Secure Connection

If you are in an environment that performs traffic inspection, you might not be able to connect to our servers. Examples, where traffic inspection interferes with Boxcryptor:

  • Anti-virus solutions that protect internet traffic
  • Public hotspots
  • Company proxy servers
  • Malware

Traffic inspection, techically speaking, is a man-in-the-middle attack. Therefore, it is important to make sure your system or internet connection is not compromised.

Working Offline

If you already have signed in to Boxcryptor sucessfully, you can continue offline. All files will be available. However, you will not be able to alter Boxcryptor permissions or use other online features of Boxcryptor.

Proxy support

Boxcryptor inherits Window's Proxy settings, including authenticated proxies (which are authenticated on demand).

If Boxcryptor should bypass your proxy configuration, add following patterns to the exclusion list:

*.boxcryptor.com // for API access (required)
*.secomba.com // for update checks (optional)

Where can I download Boxcryptor Classic?

Boxcryptor Classic is the predecessor of Boxcryptor which has been discontinued. It is not recommended to use Boxcryptor Classic because it is not supported anymore and does not work on the latest operating system versions.

If you’re an existing user of Boxcryptor Classic you can download it here and we recommend you to upgrade to Boxcryptor as soon as possible.

Download Boxcryptor Classic for Windows here: https://www.boxcryptor.com/download/Boxcryptor_Classic_v1.7.409.131_Setup.msi Supports Windows XP, Windows 7, Windows 8.1

Download Boxcryptor Classic Portable for Windows here: https://www.boxcryptor.com/download/BoxcryptorClassicPortable_1.6.402.92.zip Supports Windows XP, Windows 7, Windows 8.1

What happens if Boxcryptor goes out of business?

Boxcryptor has been designed in such a way that Boxcryptor continues to work even if the Boxcryptor servers are not available and you're still signed into Boxcryptor. If you want to take additional precautions for the event that the Boxcryptor servers would go permanently offline, you must have the following backups:

  • Exported key file
  • Boxcryptor installer file

When these files are available, you will always be able to access your encrypted files on your own on any supported operating system - without any connection to any server. The exported key file contains all encryption keys associated with your Boxcryptor account. Important: As new keys might be added over time by Boxcryptor's integrated key management (e.g. when sharing files with other Boxcryptor users), it is recommended to regularly export a new key file.

After installing Boxcryptor, you can use the exported key file to access your encrypted files using a local account. Learn more about exporting your keys and local accounts.

Advanced Client Configuration

Some preferences of Boxcryptor are not exposed in the user interface. While it is generally not recommended to modify these preferences, experienced users or administrators might want to do it to better tailor Boxcryptor to their needs.

How to manage the application configuration file

Boxcryptor's configuration file Boxcryptor.exe.config is located in the Boxcryptor installation folder (%PROGRAMFILES(x86)%\Boxcryptor). To make modifications to this file, open it in a text editor.

Changes in %PROGRAMFILES(x86)% require administrative permissions. If using the default text editor (Notepad.exe), it must be run as administrator to successfully save modifications. (Windows Key + type "Notepad" -> right-click on the texteditor in the search result -> Run as Administrator)

Also make sure that the result is saved as a .config file, as some Editors may append .txt.

The application configuration file is a XML based configuration with following format:

    <add key="KEY" value="VALUE" />

To change any setting defined by a key, change the associated value string.

The Configuration file is loaded when Boxcryptor is starting. If Boxcryptor is running when you modify a the config, you have to restart Boxcryptor in order for the change to be applied.

Updating Boxcryptor may revert the configuration file. Make sure to create a backup of your configuration.

List of application settings

  • EncryptByDefault (default false): New files created by applications in unencrypted directories will be written encrypted by default.

  • AlternateDataStreamSupport (default true): Support for alternate data streams. Note that ADS support is only enabled if all enabled Boxcryptor locations do support this feature.

  • EncryptDialogIncludedProcesses: A comma-separated list of processes which will trigger the "Do you want to encrypt" Dialog when creating files in unencrypted directories.

  • SupportedBackupProcesses: A comma-separated list of processes which that will receive backup-optimized file system I/O such as early downloading on-demand files.

  • CreateLogOnCrash (default true): Create log file in %LOCALAPPDATA%\Boxcryptor\Crash Logs upon crash.

  • ProcessNamesPreventingShutdownOnSessionEnd: A comma-separated list of all processes that need to be closed before Boxcryptor closes on session end to prevent data loss on files open via the Boxcryptor volume.

  • DisableAutomaticUpdates (default false): Prevent automatic updates and also suppress any update notifications.

  • DisableExplorerQuickAccess (default false): Disable the creation of the Boxcryptor quick access icon in the Windows Explorer's navigation pane.

  • CustomSettingsPath (default ""): A custom path where Boxcryptor stores it's user settings. Can contain environment variables. See Teams/Deployment/Custom Settings location for more information.

  • CefCommandLineParameters (default {}): Provides the ability to transfer command line parameters in JSON format to the chromium based web rendering engine (CEF).

  • EnableTerminalEnvironmentMode (default false): Predefines and restricts certain Boxcryptor settings to be compatible to thin clients (Terminal / Citrix Server).

  • RefreshUserPeriodMs (default 15000): Defines the period in milliseconds in which the client synchronizes with the Boxcryptor servers.

  • DisableInitialTutorialAndTour (default false) Permanently deactivates the automatic display of the tutorial and the introduction.

Outdated Clients

We regularly release new versions of Boxcryptor with new features, better stability and overall improvements and retire outdated versions over time. On September 30 2018, the following versions have been retired:

  • Boxcryptor for Windows 2.22.706 and older
  • Boxcryptor for macOS 2.19.907 and older

When you try to use a retired version, you will not be able to use Boxcryptor and receive one of the following error messages:

This client is invalid or outdated. Please upgrade to the latest version.

The client id is invalid!

This is no secure connection

The remote certificate is invalid according to the validation procedure

Boxcryptor can't establish a secure connection to the Boxcryptor server.


Download and install the latest version of Boxcryptor from here. Afterwards you will be able to continue to use Boxcryptor.

If you still see the error message This is no secure connection, the problem lies elsewhere. Check out I Cannot Connect to the Boxcryptor Servers.

I am using Windows XP or Mac OS X 10.13 or earlier

Current versions of Boxcryptor require Windows 7 and later or macOS 10.14 and later. As all earlier operating system versions are not supported by Apple or Microsoft anymore, we recommend affected users to update their operating system to a newer version as soon as possible in order to stay safe.

Using unsupported operation systems poses a huge security risk. You really have to update your operating system for security-related use.

I cannot update to the latest version

Note: If you are using Windows, please look into I Cannot Update or Uninstall Boxcryptor first.

If for any reason you cannot update to the latest version and can't access your encrypted files anymore, you have the following options:

Boxcryptor Portable

Boxcryptor Portable does not require any installation and can be used to access and decrypt your encrypted files without administrator rights. Download Boxcryptor Portable here.

Key Export

You can export your keys from our server and use a local account to sign in to your outdated Boxcryptor version without requiring a connection to our servers. Learn more here.

I cannot sign in due to too many connected devices

Sign in to your account at boxcryptor.com and remove a device which is no longer needed. Then try again to sign in.

Cannot open some files

There may be situations where files appear to be inaccessible. This can have multiple reasons:

Boxcryptor Access Issues

On desktop some Applications or the file browser shows a message with Invalid parameter when trying to open a file.

  • Boxcryptor is eventually signed-in to a wrong account. → Check the account info in the Boxcryptor settings and compare it with the Boxcryptor permissions.
  • The user has no Boxcryptor permissions on the file. → Make sure the user has physical access to the shared file, has Boxcryptor permissions correctly set and the latest permission changes of the file have been synced. Learn how to set permissions here.

Filesystem Permissions Issues

Files are read-only or "permission denied" is displayed. Change files system permissions so your user can (physically) access them.

Sync Issues

"Bad padding" issues, empty physical files or inaccessible folders due to an empty Folderkey.bch file.

File open shows "Found invalid data while decoding" and the .bc file is empty.

Folder cannot be opened "Found invalid data while decoding." is displayed in the permission settings.

There has been an incompatibility with Dropbox in the past that could create "broken" content for smaller files because Dropbox did not sync the last file change.

  • restore an older version of the corrupted file via the file history of your cloud storage provider.
  • for folder issues, delete the empty Folderkey.bch file and re-encrypt the folder.

To make use of Windows Search / Cortana to search within Boxcryptor encrypted files, following advanced settings are required:

  • Mount as fixed drive
  • Mount for all users
  • Mount in Windows Mount Manager

Then, the Boxcryptor drive can be added to the Windows Index Service as described here.

Problems with Windows 10 ≥ Build 2004

Due to some changes in Windows 10 Build 2004, the Windows Search Indexer has to be restarted to successfully detect the Boxcryptor drive. This has to be done prior to adding the Drive to the Index service and also after every computer start.

Restarting the Windows Search index can be done automatically by creating a Task in the Windows Task Scheduler or using our predefined Restart Windows Search Index Task (right-click ➡ save as).

To learn howto import the task into the Task Scheduler, take a look at Microsoft's Documentation here.

Adding the Boxcryptor drive to the Windows Search Index can result in severe CPU load and performance degradation as Windows is indexing all files in the Boxcryptor drive. In addition, content that is actually encrypted can end up in the unencrypted Windows search index.

There is a File Called FolderKey.bch in my Cloud Storage. What is This?

Boxcryptor creates a FolderKey.bch file when a folder is encrypted. It contains encryption metadata for its parent folder and helps Boxcryptor to maintain the encryption hierarchy. This file is not visible within the Boxcryptor drive.

Does it Leak Sensitive Information?

The FolderKey.bch does not contain any sensitive information. Only .bc files contain sensitive information — and these are encrypted.

What Happens When I Lose it?

Dont't worry, you will not loose any data or access to files. All crypto-required information is stored directly within your encrypted *.bc files.

The downside of losing that file is that Boxcryptor no longer perceives the parent folder as encrypted. As a consequence, new files in this folder will not inherit the encryption setting.

There is a File Called .bclink in my Cloud Storage. What is This?

The file helps to verify the account when linking accounts to use features like Whisply.

If the file doesn't exist, the user either used a different account for linking or the sync client is not turned on/syncing.

Does it Leak Sensitive Information? Can I delete it?

The file does not contain any sensitive information. It is not necessary and can also be deleted. However, it may be generated again automatically.