Hi Michael,
Sorry for the inconvenience this is causing.
Given the situation, I want to confirm some information first:
1. Which subscription are you using? If it is an Office 365 consumer subscription like Office 365 Home, Personal, etc, it is suggested you visit our consumer dedicated forum to get the issue address more effectively, since the engineers there have more resource and channels to help the users.
http://answers.microsoft.com/en-us/office/forum/office_365hp-excel?sort=lastreplydate&dir=desc&tab=Threads&status=&mod=&modAge=&advFil=&postedAfter=&postedBefore=&threadType=All&tm=1422150144383
Click Participate> Ask a Question to open a new thread.
2. If you are using the Office 365 Business subscription, please try the workaround in the following article and let us know any update:
http://community.office365.com/themes/groups/generic/wikis/page.aspx?WikiApp=exchange&WikiPageKey=5867.outlook-for-mac-devices-known-issues&GroupKeys=en-us/
Thanks,
Kevin Huang
