endnote not functional

I recently upgraded from End note 9 to Endnote 10.2 - and have had nothing but problems. I lost the Endnote10.2  add in tab in MS word 2007 when I tried to merge documents and libraries today.

Despite trying FAQ options nothing worked. I then tried to uninstall and reinstall. Also won’t let me uninstall- the message box tell me that the patch package could not be opened [the 10.2 patch which I have downloaded and was running - verify that it exists and it is genuine. so I reinstalled endnote 9, but it give me an error when trying to change the style.

I am happy to uninstall everything and start again - either version, but not sure how to do this as the system overrides everything.