Run a batch file in Task Scheduler to restart dropbox on a regular basis, see: https://gist.github.com/honktang/3774238 . Personally I have problems with this, it seems to sometimes open two instances of dropbox, and sometime that crashes. Not sure why. Seems like a task scheduler issue on my behalf, because the batch file works fine.
Run a batch file in Task Scheduler to delete the symbolic links and then recreate them. I put like a 5 seconds timeout between deleting and recreating. It triggers Dropbox since you're actually deleting a file (symbolic link) in the dropbox folder. Since you quickly remake the links, it also doesn't actually push all the file to the cloud again.
Not tested, but instead of using Task Scheduler with the above, and performing the task on a given interval, you could use some third party software to monitor the target folder for changes and run the batch file only when necessary. Depending on the frequency of use, that may be more resource efficient than using a timer.
Use Boxifier. I don't like it that you have to have all your symbolic links in a Boxifier folder though. But it works brilliantly.
@echo off rmdir C:\Dropbox\Pics mklink /j C:\Dropbox\Pics C:\Files\Pics