you can just re-install it. Acrobat can be very fussy about the order in which it's installed - it should be installed AFTER everything else that uses it (or thinks it can!! LOL!)
Second option would be to go to Add and Remove Programs in the Control Panel. If Word is installed as either stand-alone, or as part of Office, you can repair it's installation by clicking on the Change/Remove button. It will show you your options. Repairing the Word installation is sometimes easier than re-installing Acrobat and all it's updates!
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