Microsoft Office Document Problems with Downloaded Files.
This article relates to Microsoft Office preventing a downloaded document from being opened and getting the following message or a message similar to the one below. The message may repeat itself quickly and you may need to use task manger to exit the program or you may need to restart your computer. Affected downloads may be from Canvas, Google Email, or other source on the internet.
Unfortunately this is a known issue, that was caused by one of Microsoft's updates. The fix will come from Microsoft in another of their updates. In the meantime there is a workaround.
Before attempting to open the document
1: Right Click the document and select properties.
2: Place a Check Mark in the box labeled Unblock. Then Click Apply.
3: Now open your document as normal.