there may be a way...
found on http://support.microsoft.com/kb/2439384
Method 1
Download and install the Office for Mac 2011 trial.
When the "Welcome to Office:Mac 2011" screen appears, select the Enter your product key option.
Read the Software License Agreement, and then click Continue.
Enter the product key from the retail Office for Mac 2011 package you purchased.
Click Activate to convert the trial to a full retail copy.
worse case scenario for most issues, call apple - 1.800.275.2273 (APLCARE)
found on http://support.microsoft.com/kb/2439384
Method 1
Download and install the Office for Mac 2011 trial.
When the "Welcome to Office:Mac 2011" screen appears, select the Enter your product key option.
Read the Software License Agreement, and then click Continue.
Enter the product key from the retail Office for Mac 2011 package you purchased.
Click Activate to convert the trial to a full retail copy.
worse case scenario for most issues, call apple - 1.800.275.2273 (APLCARE)