Open the Windows Add/Remove Programs control panel. If you have any ChemDraw/Excel patches already listed, please uninstall them first. Next, download and unzip the installer. Once unzipped, run the CambridgeSoft_ChemDraw_For_Excel_Patch_12.02.msi file to start the installation. This installer should replace the necessary files if you had a previous 12.0 Excel installation (again, you must uninstall any ChemDraw/Excel patches first).

Download this installer file to your hard drive. Uninstall your current 11.x version using the Add/Remove Programs control panel. Double click on the file you downloaded. This will start the installation. This is a complete install of the ChemDraw application. Use your original 11.0 serial number to activate, if prompted.