It has been relocated the a new folder under your user account on Windows. (I assume you’re on Windows.)
However, in SU2014 we updated the Ruby interpreter from 1.8 to 2.0 and that cause a number of extensions to not work any more without modifications. Most extensions are up to date and will work fine, but there are a few still lingering that doesn’t work.
I would generally recommend fresh installation to ensure you get the up to date version. If you install via Extension Warehouse it make the process easier and it will make sure your extensions are up to date.