However, Word is unavailable, not installed, or is not the same version as Outlook.
The Outlook e-mail editor will be used instead.
An OLE registration error occurred.
The program is not correctly installed.
Run setup again for the program.
I personally received this warning pop-up when selecting the Send/Receive button.
To have a go at fix this problem, perform the following steps.
You should get a response that says the registration succeeded.
Select OK and try Outlook again.
Thanks to Somajde for this fix.