If the problem arises that someone needs to open a file extension in word, but it opens up in textedit from an outlook attachement follow these steps.
The problem is occurring because the computer defaults unspecified file extensions to open with textedit. To solve:
Open the finder and right click on the extension file and select More Info
Navigate to the Open With drop down tab, and select Microsoft Word
*Make sure you select the change all option*
To double check, double click on the attachment in outlook, and clicking on the preview tab. In the preview window it should give the option in the upper right hand corner to open in Microsoft word.
*Note: This worked for opening RTF file extensions in Word, and should work for other file types not labeled .doc or .docx. Additionally, this should work for opening file types in other programs.