Hello,

As I didn't found any forum for the Mac Preview version of office I'm posting this here.

I hope to find someone who will help.

When using one of the Microsoft Office 2016 application for the Mac (Preview), Im randomly prompt to authentification  (a very clean pop-up windows that requests "Authentication required for the server: office15client.microsoft.com")

1. I cannot use the appliction (even with a document open in background) unless I deal with the pop-up"
2. This happens only in the Corporate Network (the is a proxy) - never at home.
3. If I click on cancel the prompt goes away, and come back (3 times generally)

4. If I try to authenticate Im always re-prompt with the same pop-up without any error message (Ive tried up to 6 times )

I have no control over the proxy ... so please don't post any solution involving Whitelisting ;-)

Thanks in advance to anyone that could help.

Hi,

So this happens only in the Corporate Network behind the company proxy.

Office need to connect to Office service server during use. Might be your proxy server setting is blocking Office from connecting to the Internet. I would suggest you check with the IT/system administrator at your company for further help on the issue, make sure that Office services can connect to the Internet through that proxy server.

Or if you do not rely on Office online functions at moment, such as cloud storage, etc. You can try disabling the option of Allow Office to connect to the Internet temporarily and see if issue persists:

1. Open your Office program, say, Word.
2. Click File > Options > Trust Center > Trust Center Settings
3. Click on Privacy Options from the left pane.
4. Untick the check box before "Allow Office to connect to the Internet"

By the way, this is the forum to discuss questions and feedback for Windows-based Microsoft Office client. Since your query is directly related to Office for mac, I would suggest you to post in the dedicated forum of Office for Mac Preview, where you can get more experienced responses:

http://answers.microsoft.com/en-us/mac/forum/macofficepreview

The reason why we recommend posting appropriately is you will get the most qualified pool of respondents, and other partners who read the forums regularly can either share their knowledge or learn from your interaction with us. Thank you for your understanding.

Ethan Hua

Forum Support