Instructions for successfully completing step #3 are here:

I am leaning towards approach (A), but any caveats? Opinions? CAVEAT: Cannot simultaneously mount NTFS-3G readwrite AND use Parallels at the same time. Run Mac version of Dropbox, mount via NTFS-3G and access Dropbox folder Run Windows copy of Dropbox pointing to Dropbox folder (B) Move my Dropbox to a Windows NFTS volume. Safe to run Mac version of Dropbox regardless of whether or not I am running Parallels. Run Mac version of Dropbox, and use Parallels Shared Folder, pointing to the Dropbox folder via Parallels Shared Folder. * When booted to Windows via Parallels profile Run Windows copy of Dropbox, pointing to the Dropbox folder on HFS volume * When booted to Windows via Boot Camp profile (Or install MacDrive - another HFS+ driver) Install a Windows HFS+ driver in the Boot Camp profile (A) Keep my dropbox folder on the Mac volume (HFS filesysstem) I've successfully accomplished (1) AND (2). (3) Access same dropbox folder from Windows XP/7 in Boot Camp (native bootup) (2) Access same dropbox folder from Windows XP/7 in Parallels (virtual bootup) (1) Access same dropbox folder from MacOS Sometimes I have to go to native Boot Camp for a few reasons (example: DirectX 10/11 videogames, max Windows development performance, etc.) (NOTE: It's possible to boot the same copy of Windows in either Parallels and Boot Camp, when following instructions for a dual-hardware-profile installation, found in Parallels forums) However, now I need to access the same Windows XP installation via Boot Camp. I currently have my Dropbox set up on my Mac, and have successfully accessed the Mac Dropbox folder in Windows XP via Parallels Shared Folder. One of my Dropbox clients is on a MacBook.

Dropbox update for mac os