Thanks Chad, I have downloaded the latest trial and the Facebook login is now working fine. Although it looks like that the Twitter authentication has been affected. When I click the 'Sign In with Twitter' button, this error message appears:
"A critical error has occurred.
Invalid postback or callback argument. Event validation is enabled using
in configuration or <%@ Page EnableEventValidation="true" %> in a page. For security purposes, this feature verifies that arguments to postback or callback events originate from the server control that originally rendered them. If the data is valid and expected, use the ClientScriptManager.RegisterForEventValidation method in order to register the postback or callback data for validation."
Ver:4.10.30.29614
I had made no further changes to the Twitter integration settings, and it was working fine prior to installing the latest version.
Have you encountered this before?
Cheers