For some reason BoxCryptor Classic dropped support for OSX El Capitain and only option is to upgrade to version 2, which in my personal opinion is inferior as it does not support ENCFS.
If you have upgraded to OSX El Capitain and can no longer open your BoxCryptor Classic .BC containtainers, you can manually enable BoxCryptor Classic support in OSX El Capitain.
- Download an older version of Boxcryptor Classic. I used 1.5.409.246 (https://www.boxcryptor.com/download/Boxcryptor_Classic_v1.5.409.246_Ins…).
- Install the application and open it once (you need to open it before modifying so Gatekeeper doesn't complain to you).
- Close out Boxcryptor Classic
- Open Terminal and Run the following command:
ln -s /Applications/Boxcryptor\ Classic.app/Contents/MacOS/Filesystems/bccfs.fs/Contents/Extensions/10.9 /Applications/Boxcryptor\ Classic.app/Contents/MacOS/Filesystems/bccfs.fs/Contents/Extensions/10.11 ln -s /Applications/Boxcryptor\ Classic.app/Contents/Resources/bccfs.fs/Contents/Extensions/10.9 /Applications/Boxcryptor\ Classic.app/Contents/Resources/bccfs.fs/Contents/Extensions/10.11
If Gatekeeper gives you a message saying Boxcryptor Classic is corrupted, open System Preferences -> Security & Privacy and switch "Allow apps downloaded from" to "Anywhere". Open the app, then switch the setting back.