Password Protect / Encrypt

Is there a way to password protect a folder, so once I enter it in the web interface of the MBL the folder gets decrypted.

I also tried Truecrypt, but this seems not to be a very stable solution.

It happened to me a couple times that when I copied a large file to the Truecrypt container, the copy process stopped without any reason. Then I only got a network error and I had to restart the whole MBL again to mount the container again.