I have had the most success using Yosemite Cache Cleaner doing a “Light Cache Cleaning” as noted below. It seems that the issue does re-occur periodically. Update 02/09/15: Please be sure to read through (and leave) comments below. I have only tested one way that actually worked for me (which I noted below). However, instead of sitting and waiting to see if a common solution would come available (and you know that Microsoft WILL eventually release a patch to correct the issue), I wanted to try to find some other solutions on my own and quickly. Unfortunately, what may work for some doesn’t always work for others. Possible Ways to Fix Mac Office 2011 Crashing in Yosemite Supposedly these crashes have been occuring sporadically even back to some Yosemite betas. I went searching for a solution on various forums but only seemed to find other people encountering the same issue. It didn’t matter if I opened a document directly or one of the Office applications, within a few seconds, the Office App would crash. Every time I launched Word, Excel or PowerPoint, the app would crash after a few seconds with an error asking if I wanted to recover my work, reopen the Office app and send the error to Microsoft. Recently, my version of Office for Mac (Office 2011), started crashing on my MacBook Pro.