Yes, there is always an error message. Sorry for the german text. It says that Microsoft Word must be stooped because of a problem. They apologize for any trouble.

When I click on "further informations", a big list pops up, with these informations for example:
Microsoft Error Reporting log version: 2.0
Error Signature:
Exception: EXC_BAD_ACCESS
Exception Code: KERN_PROTECTION_FAILURE (0x000000010dd44041)
Date/Time: 2016-10-18 16:43:19 +0000
Application Name: Microsoft Word
Application Bundle ID: com.microsoft.Word
Application Signature: MSWD
Application Bitness: x64
Application Version: 15.27.0.161010
Crashed Module Name: unknown
Crashed Module Version: 15.27.0.161010
Crashed Module Offset: unknown
Blame Module Name: CocoaUI
Blame Module Version: 1.0.0.0
Blame Module TimeStamp: 0x57fb802e
Blame Module Offset: 0x000000000001c339
StackHash: 4db5
Application LCID: 1031
Extra app info: Reg=en Loc=0x0407
Crashed thread: 0
I installed now Office 2016 on my iMac and there is the same issue with Word. I think it is a specific problem between Word and iCloud Drive on Yosemite.
But I will update my MacBook now and then I will see if the problem is solved or not.