Two users sharing Boxcryptor volume on a Mac with 'fast user switching'

michael.wenyon

We want to share a single Boxcryptor volume between two users of the same Mac computer. Both users may be logged on at the same time, by using something called 'fast user switching' on the Mac.

User 1 creates a Boxcryptor volume, with a Boxcryptor folder on Dropbox which they 'share' with User 2. Both users now have a copy of the latest encrypted folder in their Dropbox folder.

So the first user logs on to the Mac and mounts the volume 'Boxcryptor' for example.

The second user logs on via 'fast user switching' (first user still logged on). But User 2 is unable to mount 'Boxcryptor' because the Mac system gives an error message that the volume is already mounted (as it is, by User 1, although it is not visible/accessible to User 2).

Here is what I think is the solution:

In Boxcryptor's Advanced Preferences, User 2 can 'delete' the volume Boxcryptor (click 'minus'), and then click 'plus' to add a new volume. This new volume can point to the same, shared, encrypted, folder in Dropbox, but it will be given the name 'Boxcryptor-2' (for example, any other name besides 'Boxcryptor').

On entering the password, this volume Boxcryptor-2 mounts OK. It appears to contain the same decrypted files and folders as User 1's volume 'Boxcryptor', and User 2 can now read and write files to it. Changes made to a document by User 2 are seen later by User 1 when they 'fast switch' back to their account.

This works for me.

My question: is there any reason not to do this?

Adrian

Hi Michael,

the reason for this is that you can't mount two volumes with the same name.

Two solutions for this that won't require any of you to remove/re-add the volumes each time you want to use it:

1. Each user set-s it's own volume label... for example BoxCryptor-1 and BoxCryptor-2

2. In Preferences window, click Settings button on the toolbar and check "Add account name prefix....." (at least one user should do this)

Best regards,
Adrian.

michael.wenyon

Option 1 is what I was using, different label names for the mounted volumes.

Option 2 I just tried for both users, and now it seems to work so that each user sees the volume mounted with the same name: is that how it is supposed to work? That would be good and will be my preference, I think.

michael.wenyon

For me there is a little problem in the way 'Add account name prefix...' works.

I am using a financial program (Home Accountz) written in Java, which stores the file path to the last open file and always tries to re-open it. Although using the option above shows me a volume icon with the simple name I originally gave to the volume (e.g. BoxCryptor), the file path calls the volume 'michael-BoxCryptor', for example.

This would not be a problem except that when I first turned this option on, my program looked for the last-opened previous file path. Again, the program itself should be written in a way that I can set a new file path, but for some reason (I am consulting the developer over this issue) it crashes almost irreparably when it cannot find the file path it expects. To recover, I had to restore my system from a SuperDuper! clone I made 24 hours ago, it was that bad.

My workaround for the moment was to open a non-encrypted file in Home Accountz, close it, and then enable the 'Add account name prefix' option and mount the BoxCryptor volume. Then, with the new file path in existence, I opened the original file on the encrypted volume from within Home Accountz (File>Open). Of course as I navigated through the file browser to my original file I saw the volume with its abbreviated name, but when I later opened Properties in the open file, it showed its 'true' file path including my username prefix.

I'm not sure if BoxCryptor behavior should be different. Immediately, I think the Home Accountz program needs to be able to recover from a missing volume problem without a complete hard disk restore.

Or, maybe there could be an option that BoxCryptor 'honestly' shows the volume name in Mac Finder, complete with the username prefix.

PS: I notice with the username-prefix option 'on', using 'Get Info' on the BoxCryptor volume shows the 'true' path, including the username prefix.

michael.wenyon

Also, with my previous setup (using MacFusion, EncFS, MacFuse etc) I used to get the decrypted volume named the same for both users on this computer, once they had each mounted it.

Somehow, it was not automatically visible to User2, when User1 mounted it, unless User2 mounted it themselves.

I think I read in the history document for BoxCryptor that at one time both users would have seen and had access to the encrypted volume. That would be fine for me, especially if they then both see the same volume name and same file path. Could that be offered as an advanced option?

michael.wenyon

Finally (I hope), for me, it will be better to use the default setting of BoxCryptor (no username prefix), and to give the mounted volume the same name for both users of this computer.

It has the relatively minor inconvenience that User1 will have to unmount the encrypted volume before User2 can log in and mount it, but that then has two advantages:

1. the system filepath to files on the encrypted volume is identical for both users, and expressed by a path without either username in it, and

2. it creates a kind of 'lock' where there is no danger that User1 has a file open and unsaved when User2 mounts the volume and accesses the same file

A more common scenario is that User1 is logged on to Mac1 and User2 is logged on to Mac2. Both then mount the encrypted volumes on their own Macs, with the same mounted name, and with volume settings pointing to the same BoxCryptor folder--a folder they 'share'--in DropBox. There could be some problems where both users try and open the same file simultaneously, but some programs, like Excel, have lockfiles that warn you most times if there is a danger of this.

Charly22

Hallo,
ich habe Boxcrypter seit kurzem auf einem Windows7 Rechner in der kostenlosen Version testweise installiert und ein ähnlichen Problem wie Adrian auf seinem Mac entdeckt.

Auf unserem Rechner arbeiten zwei User abwechselnd.
Das verschlüsselte Boxcrypter Volumen liegt auf einen NAS.
Das Boxcrypter Volumen wird für beide User unter dem gleichen Laufwerksbuchstaben eingebunden und von beiden benutzt.
Erweiterte Einstellungen, Papierkorb aktiviert.
Zunächt gratulation zu dem Tool, ich habe vieles probiert aber Boxcrypter macht einen wirklich guten Eindruck.

Nun so lange jeder User sich abmeldet bevor sich der andere anmeldet ist alles ok.

Bleibt der erste User jedoch angemeldet und der zweite User meldet sich mit "Benutzer wechseln" ebenfalls an kommt die Meldung "Laufwerksbuchstabe wird bereits verwendet".

Klickt man auf "Beenden" ist das Boxcrypter Volumen mit dem vorgegebene Laufwerksbuchstaben trotzdem vorhanden jedoch fehlt das grüne Boxcryptersymbol und der zweite User kann auch auf dieses Schreiben. Es ist jedoch so das die vom User2 geschriebenen Dateien als Besitzer User1 haben was dann in unserem Fall zu Rechtekonflikten führt.

Klickt man auf "Einstellungen" und vergibt einen anderen Laufwerksbuchstaben ist das Boxcrypter Volumen unter beiden Laufwerksbuchstaben vorhanden. Jedoch einmal ohne und beim neuen Laufwerksbuchstaben mit dem grünen Boxcryptersymbol.
So lange der User2 nur das Boxcrypter Volumen mit dem neuen Laufwerksbuchstaben verwendet ist er auch der Besitzer der Datein, also alles ok.

Unschön ist das das Boxcrypter Volumen (Anmeldung User1) überhaupt für User2 zu sehen und zu benutzen ist. Es wäre hilfreich wenn das Boxcrypter Volumen nur unter einem neuen Laufwerksbuchstaben oder gar nicht zu sehen ist oder noch besser beim Benutzerwechsel das Boxcrypter Volumen zwangsweise getrennt wird.

Mache bzw. verstehe ich prinzipiell etwas falsch?

Gruß Charly