Processes in Microsoft 365 for setting up Office apps, redeeming product keys, and activating licenses.
You may also refer to the following Microsoft Article to test for damaged Office for Mac installation media and check if this helps to resolve the issue:
http://support.microsoft.com/kb/282981
Check if the disc works on another computer. If yes, copy the image of the disc and transfer it to the problem computer through a flash drive and try installing it.