I just upgraded my 9.0 version of Chem3D and now MOPAC is gone.

I just upgraded my 9.0 version of Chem3D and now MOPAC is gone.

Due to licensing issues, we are no longer able to install the MOPAC application as part of our ChemOffice suite. You can however preserve the version of MOPAC that came with our 9.0 release.

If you have already run the 9.0.x upgrade installer on your system, you will need to uninstall 9.0.x and reinstall the 9.0.0 version. Once 9.0.0 is reinstalled, follow these steps:

1. Copy the following files from your CambridgeSoft\ChemOffice2005\Chem3D\C3D Extensions folder:
   CSMopac.exe
   MopacLib.dll
   The MopacJob folder and all of its contents
2. Place the copied files into a temporary folder on your hard drive to save them for later use.
3. Install the 9.0.x product using the installation wizard provided.
4. After installation is complete, copy the files saved in Step 2 above into the new CambridgeSoft\ChemOffice2005\Chem3D\C3D Extensions folder.
5. Locate the .REG file in the Readme folder on your CD-ROM or if you downloaded your 9.0.x update, you can download the .REG file here:

   http://media.cambridgesoft.com/support/9/Mopac_Extension_9.0.0.zip
   and then unzip this file.

6. Double click the .REG file, which will enter the following key into your system registry:
   [HKEY_LOCAL_MACHINE\SOFTWARE\CambridgeSoft\Chem3D \9.0\Extensions\CSMopac9.Extension] @=""
7. From the Windows Start menu, select Run.
8. Click and drag the CSMopac.exe file into the Run window's command line area, this will enter the full path to the CSMopac.exe into the command line.
9. Click in the command line window and move the cursor to the end of the line.
10. At the very end of the command line, after the last quotation mark, type a space character followed by /regserver.
11. Click OK on the window to run the command. This will allow the Mopac extension to register itself on your system. Please note: You will not see any dialogs at this time; the registration is silent.
12. Upon launching Chem3D, the Mopac menu extension should now be present.