This issue started happening yesterday.
Users are reporting that if they try to open an Office document this works fine. However, if they try to open a previous version they get either a blank application open with no document, an error saying it cannot open the file(which looks like it's generated from the Application, not SharePoint) or they are continually prompted for a login and password.
This is happening on all sites using all browsers. So previous resolutions on Technet which suggest this is an IE issue do not apply here.
As far as I can tell, no changes have been made to the Farm and no security updates have been rolled out.
The ULS Log didn't provide anything useful and I'm of a mind that this is an issue with Office rather than SharePoint but I cannot prove it.
If I download a local copy of an older version of the document it still does not open, which further strengthen my belief this is external to SharePoint.
I installed Libra Office to a test machine and if I try to open an older version of a Document using Libra it works.
I don't know if this is significant but I will mention it anyway. The latest version of the file opens in the Browser, but the previous versions attempt to open in the Client Application.
Any help/suggestions gratefully received....