If login issues occur when connecting to SharePoint or it continually prompts for a login please try this solution.
- Open Registry Editor, go to HKLM\Software\Wow6432Node\SimpleIndex\Misc
- Create a String setting called DisableSharePointForms and set the value to 1
- Run again and re-enter the login information.
- After this it should logon to SharePoint automatically without requesting the logon information.