Outlook may not be installed with a newer version of Outlook
You are not able to install Outlook, and the following error occurs during the process:
Microsoft Outlook  may not be installed with a newer version of Outlook. If you continue, Microsoft Outlook  will not be installed.
This problem might be caused by the existence of Collaboration Data Objects (CDO) or by an old MAPI profile in your environment. To solve the problem, you need to:
- uninstall MAPI Client and Collaboration Data Objects (MAPI CDO) from your environment;
- if this does not help, remove the old MAPI profile from your environment.
To uninstall MAPI CDO from your machine, go to Add or remove programs in the Control Panel and remove the software in the usual way. You should now be able to install Outlook.
If you are still not able to install Outlook, you can try to solve the problem by deleting your old MAPI profile. Follow the steps below:
- Open the Start menu, type Run and press Enter (or press the Windows logo key+R keycombination to launch the Run command (Fig. 2.).
- Type regedit and click OK.
Fig. 2. Opening the Registry Editor.
- Navigate to the proper registry key. It should look similar to the one below (see Fig. 3.):
HKEY_CURRENT_USER\SOFTWARE\MICROSOFT\WINDOWS NT\CURRENTVERSION\WINDOWS MESSAGING SUBSYSTEM\PROFILES
Fig. 3. Finding the MAPI registry key.
- Select the key named Profiles (see Fig. 3.) and press the Delete key (or use the shortcut menu). The confirmation appears (Fig. 4.).
- Click Yes to confirm. Installation of Outlook should now be possible.
Fig. 4. Confirming the deleting of the registry key.