Windows Authentication issue with Safari 5.x in Windows 7

Question

We encounter an issue with Safari 5.x in Windows 7 as explained in this question, "Postback is not working in Safari in Windows 7" We thought it is a ViewState issue as many people encountered this before. But after reviewing too many sources, it seems that Safari 5.x has some issues with Windows Authentication in Windows as explained in these links

Problems with Safari 5.1 in Asp.Net Windows Authentication
Problem using Windows authentication in Safari5.1
Safari 5.1 & Windows authentication broken with modal dialog

Is that true that Safari 5.x has issues with Windows Authentication? If so, how to resolve it? Any idea?

Answer 1

Safari has an issue when working with Windows Authentication under IIS if Negotiate provider is enabled.

How to resolve? In IIS, go to the Authentication settings of your website. Right click on Windows Authentication, choose providers and remove Negotiate, leaving NTLM this makes everything works fine.

[References]

• AJAX POST Request Only Works Once in Safari 5
• Negotiate Mechanism article in Wikipedia shows that it is not implemented in Safari