If you get such an error:
The authentication schemes configured on the host ('Ntlm') do not allow those configured on the binding 'WebHttpBinding' (Negotiate)
If the Provider "Negotiate" is removed from the Default Website>Authentication>Windows Authentication>Providers, then the above issue occurs.
In order to overcome this issue, you need to add “Negotiate” provider for the Default website under IIS as shown below:
Once it is done, it is required to reset IIS from the command prompt for the changes to get reflected.