here's an update on this issue from our side. I can confirm this BSOD and also that it is not caused by Boxcryptor but due to a bug in Norton/Symantec Security 2015's SRTSP64.SYS driver which gets triggered when the Boxcryptor drive has been mounted. There's really not much we can do about this problem as it has to be fixed by Norton. If you are experiencing this problem, please contact Norton support so that they fix their software.
That said, there's a workaround for Windows 8 (and above) users: If the Boxcryptor drive is mounted for all users and in Windows Mount Manager, the bug is not triggered in Norton's driver and the BSOD does not appear. A short guide how to enable these mount options can be found here under "I have Norton Security 2015 installed and have problems with Boxcryptor":
[A more technical explanation for anybody interested: By default Boxcryptor creates a non-PnP virtual disk and the SRTSP64.sys driver sends a PnP request to the disk after it has been mounted. This request is being answered with "STATUS_INVALID_DEVICE_REQUEST" by our CBFS driver as non-PnP disks do not support PnP requests. It could be that the SRTSP64.sys driver does not correctly check the result and then crashes. The workaround causes Boxcryptor to mount the disk as a PnP virtual disk (instead of non-PnP) and then SRTSP64.sys does not crash.]