This page shows up high on Google’s list, so at the risk of being accused of necro-posting, I’m offering an answer to those that come searching for this five year old simple question:
Versions not listed may follow one of the models below.
EndNote 6
After backing up all data in EndNote folder
Reset Preferences (see below) and install new version (if desired)
EndNote 8
After backing up all data in EndNote folder
Launch Endnote > Customizer
Select the “Uninstall” check box and click “Next”
Drag the EndNote Folder to the Trash
Reset Preferences (see below) and install new version (if desired)
EndNote 9, X, and X3
After backing up all data in EndNote folder
Launch Endnote
Select EndNote > Customizer
Select the “Uninstall” check box and click “Next”
Drag the EndNote Folder to the Trash
Reset Preferences (see below) and install new version (if desired)
EndNote X5
After backing up all data in EndNote folder
Launch Endnote
Select EndNote > Customizer
Click the “Uninstall” button
Confirm that you really want to kill EndNote
Click Exit
Drag EndNote Folder from Applications to the Trash.
Empty Trash
Reset Preferences in EndNote
With EndNote 8 or later, do the following to reset the preferences completely:
Go to Users:[your login name with the house icon]:Library:Application Support:EndNote
Remove all files from this location (you can put them on the desktop- they will be rebuilt when EndNote restarts- when the process is complete these old files can be removed).
Go to Users:[your login name with the house icon]:Library:Preferences.
Remove the “EndNote f” folder, “com.ThomsonResearchSoft.EndNote.plist” file, and the “com.IsiResearchSoft.EndNote.plist” file (The EndNote f and the IsiResearchsoft files may not be present).
If your computer was upgraded from Mac OS 9 to Mac OS X and you had EndNote for OS 9 installed, please see **Note below.
Restart the computer.
Go to Applications: Utilities and open the Disk Utility application.
Choose your hard drive, then click the “repair disk permissions” option. Close the utility when the repair is complete.
Drag the EndNote folder from the CD or Disk Image to the Applications folder on your hard drive to install EndNote.
Open EndNote.
Go to the EndNote 8 (or later) menu; select Preferences.
Click the “EndNote Defaults” button.
Click on “Display fonts” then choose the “EndNote Defaults” button.
Click on the next option down, and click the EndNote Defaults button. Do this for each option here.
Click Save, and close this window.
Reboot your Macintosh.
**NOTE: There are additional steps if you are using Classic and OS 9 versions of EndNote, and your computer was upgraded from Mac OS 9 to Mac OS X. Go to your OS 9 system folder, and open the Preferences folder. Here, pull out all files or folders starting with “EndNote.” Place these files on your desktop. If you do not have these files, you can proceed to Step 5.