Filevault and the Google Drive application

Sorry, this reply does not answer the question. If I use, say, Dropbox, or any of a number of other file sharing services, and I have installed the Dropbox app on my Mac, then Dropbox creates a folder on my internal drive.

Does FileVault encrypt the Dropbox folder? It had better, because it's Full Disk Encryption. As the Dropbox files are encrypted, they will be synchronized (copied, in encrypted form) to the Dropbox account in the cloud.

I fear that the encrypted files will not be openable on any other device.

This reply says "when you open the files" but handily leaves out the computing device on which you are attempting the open operation. If it's iOS, or Windows, as originally asked, what happens?

Does FileVault encrypt the Dropbox folder? It had better, because it's Full Disk Encryption. As the Dropbox files are encrypted, they will be synchronized (copied, in encrypted form) to the Dropbox account in the cloud.

When you use file vault whole disk encryption, the files stored on your physical local drive (ONLY) are encrypted when written to the drive, and decrypted when opened and read from that drive for ANY Use.

So when your Dropbox App decides to synchronize a file, it uses the Mac File System to open the file and read the data, which are delivered "in the clear". The "clear" version of the data are synchronized with Dropbox. This works because you are logged in and have provided the password required for on-the-fly decryption.

If DropBox decides to encrypt your files before sending them onto the Internet, that will be done using the DropBox password, which is likely to be different from the File Vault password. Your other devices would need to have access to the Dropbox password -- the fileVault password would not be needed at that point.

If your Mac is found by the side of the road, the login and decryption password are unknown. So ALL the files on your Mac disk Drive are encrypted. If they are read (without knowing the password) they appear to be gibberish. Brute-Force discovery of the decryption key (provided you used a long-and-strong password) should take more than a decade of supercomputer time by brute force.

You can also think of this as the DropBox folder is an illusion -- it represents files not actually on your encrypted internal drive, but on the Internet. There may be local unencrypted copies stored on your Mac for your convenience, but they are likely on a different Volume.

Thank you, Grant.

I now understand that when FileVault encrypts the files, they are not changed as far as Dropbox (or any other app) is concerned.

In a (rather long) phone conversations with Apple's telephone support people this afternoon, I explained what I thought happened (all the files would be changed and Dropbox would synchronize them in encrypted form). They never corrected my misunderstanding.

Your post helped me to understand this better.

Now to another question: Are Time Machine backups encrypted once FileVault is turned on? The answer apparently is no. Time Machine external drive(s) would need to be encrypted separately (with manually entered encryption keys). See:

http://kb.mit.edu/confluence/display/istcontrib/Enable+FileVault+%28whole+disk+e ncryption%29+on+Time+Machine+backup+driv…

Time Machine backups are not encrypted by default.

If you wish, you may encrypt them. You can either encrypt the drive after making some Backups (which takes a very long time) or start a new Backup, encrypted starting with its original creation.

Your Mac will read a file to be backed up (converting it to plain text) then encrypt it with the Time Machine Backup key and store it on the Encrypted Time Machine Volume. [requires 10.7 or later.]

The late James Pond write an approachable illustrated article on this very issue:

.Pondini's Time Machine - Frequently Asked Questions -- 31. How do I set up and use encrypted backups?

(be sure you read the pink box at the end to the article)

In a (rather long) phone conversations with Apple's telephone support people this afternoon, I explained what I thought happened (all the files would be changed and Dropbox would synchronize them in encrypted form). They never corrected my misunderstanding.

Encryption (and all its implications) is a rather complex topic. If you were dealing with First-Level Responders, they do not receive special training in encryption, so the depth of their knowledge will vary widely.

For a productive discussion on advanced topics, you may need to speak to a specialist. Specialists have additional expertise in their area, but may be far less patient with low level problems (is it plugged in?). It is not clear to me whether there would be a specialist in Encryption issues available. Perhaps they have a Time Machine specialist who could discuss this with you. They may refer you back to the forums for issues not related to a specific product.

There is no conflict between FileVault and either Google Drive or Windows. When you open files they are decrypted automatically.