- I Cannot Connect to the Boxcryptor Servers
- Use self-signed Certificates for Cloud Provider
- I Cannot Move a File to an Encrypted Folder
- Camera Upload is Not Working
- Where can I download Boxcryptor Classic?
- What happens if Boxcryptor goes out of business?
- Outdated Clients
- Cannot open some files
- What is a FolderKey.bch and a .bclink file
- Recover Account Access if Second Factor (2FA) is Lost
FAQ & Troubleshooting
I Cannot Connect to the Boxcryptor Servers
Boxcryptor uses the proxy configuration provided by the Android system.
Help can be found here at Advanced Network Settings → Proxy.
Use self-signed Certificates for Cloud Provider
Connecting to self hosted WebDAV or Owncloud / NextCloud instances with self-signed certificates does not always work out-of-the-box.
For Boxcryptor to connect to your server, you must install your self-signed certificate as a user certificate on your Android device. For more information, please see here.
For self-signed certificates, the following configuration entry is required at creation to be accepted as a valid root CA:
If you own the domain, you can instead create a free and trusted certificate. For more information, see Authorities such as Let's Encrypt.
I Cannot Move a File to an Encrypted Folder
Moving files between differently encrypted folders or into a new encrypted folder always requires encrypting the files with the new folder key. Hence, Boxcryptor has to download the item, decrypt, encrypt, and upload the item again. This would present an obvious strain on your bandwidth. Since users might no expect this much data usage for a simple move/copy operation, we decided to disable the option to move and copy between encrypted folders.
Camera Upload is Not Working
If Camera Upload is not working, please try the following:
- Force quit: Do not force quit Boxcryptor using an app manager or the Android app settings, as this will also force quit any background detection. Just restart Boxcryptor to enable background detection again.
- Battery saver: If the Android Battery Saver mode is enabled, any background detection is blocked. You can start Boxcryptor to bring it to the foreground so that the detection can run, or just disable the Android Battery Saver mode.
- Battery optimization: Android automatically battery optimizes any installed app. But this may cause issues if a process - like detecting photos or videos - must run in the background. You can whitelist Boxcryptor from battery optimization by heading to the Android settings → battery → → battery optimization → all apps. Scroll to Boxcryptor, and select “Do not optimize”.
- Restart Boxcryptor: In some cases it is sufficient to restart Boxcryptor. Swipe away Boxcryptor from the Android recent apps screen and start Boxcryptor again so that the Camera Upload detection is started.
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.
Boxcryptor Classic for Android is not available in Google Play anymore but can be downloaded it here: https://www.boxcryptor.com/download/Boxcryptor_Classic_v1.5.4_Android.apk Supports Android 2.1, 3, 4
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.
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 10.14 or earlier
Current versions of Boxcryptor require Windows 7 and later or macOS 10.15 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 does not require any installation and can be used to access and decrypt your encrypted files without administrator rights. Download Boxcryptor Portable here.
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
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 parameterwhen 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.
"Bad padding" issues, empty physical files or inaccessible folders due to an empty
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.bchfile and re-encrypt the folder.
What is a FolderKey.bch and a .bclink file
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.
Recover Account Access if Second Factor (2FA) is Lost
In the case of a lost second factor for the two-factor authentication (2FA) such as an authenticator app, your mobile device in total, your security key or other hardware, you will no longer be able to sign in to your Boxcryptor account.
Ways to recover access to your account:
Re-apply the secret key from your initial setup
If you still have your secret key from the initial Authenticator App setup, you can just re-add it to your authenticator app of choice. Next to the QR Code scan method these apps usually provide a "manual" way to add a Time-based One-time Password (TOTP) account.
For reference, the secret key looks similar to:
mzwe wocd mj3d qr3f njjw g2cm grqw cvli
Use a device code
If you are still recently signed-in in Boxcryptor for Windows or Boxcryptor for macOS, You can use these devices as a second factor instead.
The second factor authentication screen will then provide you with the extra option "Use Device Code". Upon clicking on it, our apps will provide you with a temporary 8-digit pin, that will be valid for 5 minutes.
Please ensure that your Boxcryptor client is up-to-date before. You can always download the latest version here.
Also, make sure the Boxcryptor client is started and unlocked before requesting a device code.
Use a backup code
Once you set up your second factor, backup codes will be generated and presented to you. You can use these one-time codes instead of your second factor.
If you run out of one-time codes, you can regenerate new codes here.
None of the above methods apply
If you are still unable to access your account, you can also contact us to disable the two-factor authentication.
However, we need clear evidence that you are the legitimate owner of this account.
The identification will be done via video live chat, you will need the following things:
- A device with a browser installed and a working camera.
- An identification of your person (ID card, passport or driver's license).
- The valid e-mail address of your Boxcryptor account.
To pick an appointment, please visit our Booking Page.
Please provide a valid e-mail address, since it will be used for a calendar invite, further instructions and a meeting join link.
As a video chat platform, we use Microsoft Teams. You do not need a user account there. On desktop computers, a modern browser (Chrome, Edge or Safari) is sufficient. For other browsers or mobile devices, you might have to download the Microsoft Teams App:
iPhone & iPad: https://apps.apple.com/app/microsoft-teams/id1113153706 Android: https://play.google.com/store/apps/details?id=com.microsoft.teams Desktop: https://www.microsoft.com/en-us/microsoft-teams/download-app
Invalid Authenticator App Codes
If you are unable to generate a valid code despite the authenticator app working, this is most likely due to a different time on one of the systems involved.
Since these TOTP codes are only valid for 30 seconds, deviations from real time of just a few seconds can lead to registration problems.
You can check the synchronization on all participating devices by visiting the following website: https://time.is
If the time difference is more than a few seconds, we recommend that you set up the automatic time synchronization of your devices or, if necessary, perform a new one.