Resolving Dropbox hanging when relocating local folder


* Let me begin this post with saying that I’m a huge fan of Dropbox. It’s a fantastic service that is dead simple and “just works”. That said, I hit a snag with it recently that was a bit frustrating and took me some time to get straightened out.

Dropbox is a service that lets you install a small client application that watches a folder on your computer. Whenever anything is added, removed, or changed within that folder it automatically uploads that change to its servers. You can then access those files via their web interface, or on any other computer with the client installed that is associated with your Dropbox account. In this way it not only gives you an “off-site backup” of your stuff, but also lets you keep some files synced between multiple machines. I use it to keep certain files synced between my laptop, our home theater PC, and my work PC.

When I first started using Dropbox, it would set it’s root synchronization folder as ‘<user>\My Documents\My Dropbox\’. I understand this decision as most users likely put “documents” into this folder; making a sub-folder within “My Documents” a logical location choice. It was a bit of a drag for me though, as I sometimes wanted to keep code in my Dropbox. My Visual Studio solution and project names can sometimes be pretty long because I like fairly verbose namespaces and this was causing the full paths for some of my files to exceed the maximum allowed length.

Dropbox later introduced a feature allowing you to specify where you wanted the root drop box folder to live on your hard drive. This let you have a much shorter root path like “C:\My Dropbox\” which is much more conducive to my project naming conventions 🙂

When you install the Dropbox client for the first time it gives you the option to choose where you want the ‘My Dropbox’ folder to live. You can also access the ‘Preferences’ dialog at any time following the installation to change this location. This kicks off a process where Dropbox attempts to move all of your files from the current location to the new location. I performed this on my work PC the other day and encountered an error about 2/3 of the way through the process. The error informed me that I would need to re-associate my computer with my Dropbox account. After clicking ‘OK’ on the error dialog the Dropbox process hung and gave me an hourglass pointer. After a minute or two of this I opted to uninstall the Dropbox client from Control Panel and reboot my machine.

After rebooting I attempted to re-install Dropbox only to have it hang again. I opened Task Manager to try and kill the process directly but received an error stating that the ‘operation was invalid’. Performing an uninstall was the only way to get that process to stop. My next attempt was to kick off the installation process and let it run when I went home for the night on the off chance that it just needed time. I arrived the next morning to find it still hung and I was still unable to kill the process. I uninstalled again and tried using the ‘System Restore’ to roll back my settings to the day before I first encountered this issue but even that didn’t help.

I was left very frustrated seemingly unable to get Dropbox installed. On a hunch I decided to see if my uninstalls were cleanly removing all Dropbox related files. On my Windows XP machine the Dropbox installation folder was:

C:\Documents And Settings\jesse.taber\Local Settings\Application Data\Dropbox\’

I found that there seemed to be a number of files left in this folder. Trying to delete them resulted in an error indicating that at least one of them was currently in use. I checked to see if Dropbox.exe was currently running and found that it wasn’t. After drilling down a bit more I found that the offending file that couldn’t be cleaned up was ‘DropboxExt.3.dll’. It was then I had to go grab Process Explorer and do a File/Handle search to figure out that ‘explorer.exe’ had the handle to that file.

I tried using Process Explorer to close the handle, but was still unable to delete the file. I used Process Explorer to kill ‘explorer.exe’ (I love doing that) and open a command prompt. I was then finally able to delete the Dropbox folder completely. I closed out that the command prompt window, started explorer.exe again and gave the Dropbox installation one last whirl. It installed without a hitch!

I hope this helps anyone else who has this problem and stumbles across this post. For what it’s worth I later tried to re-create this issue and was unable to; the Dropbox ‘move’ operation worked perfectly on the second try.