I was battling to solve same issue and solution that worked for me:
1. Control Panel> Hardware and Sound>Devices and Printers
2. Remove External Hard Disk
3. Eject Hard Disk
4. Plug it back in
All done with dropbox running and open on the background, and boom, it triggers the pop-out \"Do you want to backup your external drive?\"
Syncing...
","body@stringLength":"415","rawBody":"I was battling to solve same issue and solution that worked for me:
1. Control Panel> Hardware and Sound>Devices and Printers
2. Remove External Hard Disk
3. Eject Hard Disk
4. Plug it back in
All done with dropbox running and open on the background, and boom, it triggers the pop-out \"Do you want to backup your external drive?\"
Syncing...
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I told Dropbox to not backup an external drive; now I've changed my mind","moderationData":{"__ref":"ModerationData:moderation_data:563076"},"body":"I'm having the same problem. Are you seriously telling me that there's no way in the Dropbox settings to enable backup on an external drive, except to nuke all my data on the external drive and reformat it? What is going on? Dropbox want us to use this functionality for our most sensitive data? I honestly cannot believe this.
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Some option to reset the list of external drives in preferences or similar would be ideal.
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