Sharepoint 2013 Document Authenication issue

[7UD9]

Hi all

 

We have a SharePoint 2013 install on-site. It's fully updated and otherwise functioning properly. I have Office Web Apps set up and that works great too.

 

I'm having an issue with Office Publisher documents, there is no Web App for Publisher so the documents open in the full Office version which is fine, except... upon opening the document the user is prompted to enter their username and password. This only happens for Publisher, other documents open without a prompt (both in Web Apps and Office).

 

This only happens on PCs that are inside the LAN and on the domain. I set up a test PC this morning which did not display the problem until I'd added it to the domain. Taking it off the domain again does not revert the issue, it persists.

 

I can access the same files from outside of the LAN (tried from my home PC) without the same problem, everything works as I expect.

 

I found the following KB article which seems to describe my problem exactly, I downloaded the hotfix but get told it's not compatible - https://support.microsoft.com/kb/943280 from what I can tell the hotfix isn't already installed and performing the necessary regedits does not resolve the issue.

 

Can anyone suggest what else I can look at?

 

Thanks