"Select the credentials you want to use to logon to this SharePoint site" after Backup restore

Question

We recently restored a site collection using Restore-SPSite. Following the restore, a new page appeared that prompted me to select the authentication provider. There is 2 choices in the dropdown and both are "Windows Authentication" (see first image below).

This happens for ANY site collection, even those I did not restore. The message of the prompt page is "Select the credentials you want to use to logon to this SharePoint site:".

There was a duplication of the authentication providers (2 providers for the same zone), which I deleted. Unfortunately, it did not resolve the issue. I'm really confused, I have no idea what may have caused this to happen. It does not make any sense to me that the command Restore-SPSite could change a configuration at the farm level.

Any help would be greatly appreciated.

Answer 1

Looks like 2 AUTH provider for single zone, could you please check

• from central admin > Manage Web Application> click on the web application and from ribbon >>> click on Authentication Provider. Check if there are multiple zone on that page
• also check if multiple Authentication provider configured for same web app, also check if you specify the Login page url
• I would reset IIS on all servers in farm
• or will clear the config cache on the server.

Answer 2

There was 2 authentication provider configured on 2 different zones (default and custom) under the same web app. I deleted the custom zone and the problem was solved. I then re-created the custom zone and tested again with a new backup-spsite and a new restore-spsite and the problem did not happen again. I suspect the configuration database used at the time of the backup was different than the config database of the target restore site collection. This was done in the context of restoring a pre-production environment to the same state as the production env.