If you want to sync Dropbox and Basecamp, the best is to sync your entire Basecamp account with a dedicated Dropbox folder and then you can just put files into <folder_name>/<project_name>/Files (attached to Project)/<category name> and new files will automatically uploaded to Basecamp.

Here is how to accomplish this:

• Go to Synchronization tab. Click on “Add Synchronization Pair”. That will take you to https://cloudHQ.net/synch_wizard
• Click on Basecamp icon

   

• Select your Basecamp account or enter your Basecamp credentials

  

• Now, just select top-level Basecamp folder: this folder contains all projects, files and messages in your Basecamp account. Or you could select just a project or portion of a project.

  

• Click on Dropbox icon

  

• In next step, select your Dropbox account or authorize new one

   

• Now, create a new Dropbox folder which will be dedicated for Basecamp project. So click on “Create Folder” and create a new folder. You can name this folder “Dropbox_Basecamp”

  

• Then select the newly created collection (that is folder “Dropbox_Basecamp” created in previous step) and press “Select Folder’.

  

• Start the sync

   

Now, cloudHQ will copy your Basecamp data into the Dropbox folder “Dropbox_Basecamp” and create the required folder structure.

So, wait for the first sync to finish; You will receive an email. 

Now, you can just move or copy files you want to upload to Basecamp into “ Dropbox_Basecamp/<project_name>/Files (attached to Project)/<category name>/” folder. And these files will be automatically uploaded to Basecamp. And each time you modify these files, a new version of the file will be uploaded to Basecamp.