Ok, this was a nasty littler error I ran into when I needed to upgrade to Excel 2010 for a spreadsheet modeling class I was taking at Harvard. I bought the Academic Version of Office Professional 2010, then the chaos began.

IN SHORT: Upgrades from Outlook 2007 to 20010 seem to have issue as Outlook 2007 in not uninstalled when upgrading from Office 2007 to 2010 even though other Office applications (Word, Excel, etc. are uninstalled if i upgraded.)

MY SITUATION: Micfrosoft Office Enterprise 2007 installed on Window 7 64bit Professional (disclaimer: only booted into to play games or use Microsoft products outside of VMWare, otherwise I am a *Nix head!)

UPGRADE PATH: Microsoft Office Professional 2010 (Academic) upgrade performed.

I performed an upgrade rather than uninstalling 2007 and doing a fresh install of 2010 because I needed to keep some Office apps that are present in the Enterprise version that are not present in the Professional version (Visio, Project, and One Note). I figured the upgrade would install the 2007 apps included in the 2010 Professional Version (Word, Excel, PowerPoint, Outlook, etc.).

THE EXPECTED: All 2007 apps not present in the 2010 upgrade were left in place (Visio, Project, & Access) and worked with no problem.

THE UNEXPECTED:Outlook 2007 was not uninstalled. When I triec to start the new Outlook it immediately crashed. If I started in safe mode like this:

“C:\Program Files (x86)\Microsoft Office\Office14\OUTLOOK.EXE” /safe

Outlook would start, but withn 2-30 seconds it would crash with a dll error such as:

“The file OLMAPI32.dll is incompatible with Microsoft Outlook. Install Outlook again” or “The file exsec32.dll is incompatible with Microsoft Outlook. Install Outlook again”

I tried re-upgrading to 2010 Professional again and rebooting. This did not resolve the issue. I tried repairing 2010 and this did not resolve the issue. After a bit of sleuthing I realized that Outlook 2007 had not been removed. I then decided to remove just Outlook 2007 from the Office 2007 Enterprise installation. Some people might not realize this can only be done by modifying The Office 2007 install… “Outlook 2007” is not going to be in your list of installed programs.

Uninstall like this in Windows 7:

To do this is Windows 7 you need to:

* Go to Control Panel
* Under the “Programs” heading Select “Uninstall a program”
* Right click on the “Microsoft Office Standard 2007 item in the resulting “Uninstall or change a program” window and select the ‘Change’ option per the image below:

You will  get the option to ‘Add or Remove’ Features’:

Click the radio button beside ‘Add or Remove Features” then click Continue.

As in the image below, X out the “Microsoft Office Outlook” application by clicking on the down arrow and selecting the ‘Not Available” option. Once X’d out, click on the Continue button:

Next you will see this Configuration Process Screen:

And then this success screen:

But don’t get excited yet… we’re not quite done. Reboot. Now we fix the dll error.

* Proceed again to the “Uninstall or change a program”  window (see first image above)
* Right click on “Microsoft Office 2010” in the list
* Select “Change” (as you can see in the first  picture above for Office 2007)
* Select the ‘Repair” option as pictured below then press “Continue”

This well be followed by the “Configuration Process” notification screen.

After this completed, Outlook 2010 was repaired and has functioned normally for some time now. The Office 2007 legacy apps (Visio, Project, etc.) configure to work without problems.