Originally posted: https://bouncethebox.wordpress.com/2009/05/02/1073741428-0xc000018c-displayed-in-ie-when-accessing-sharepoint-site/
-1073741428 (0xc000018c) identifies an issue with a trust to your domain. Generally speaking, your domain controller is unable to contact/connect to the domain controller this user is coming from to authenticate the users credentials. If users are receiving this message in their web browser when accessing your portal, the best thing to do is validate the trust between your domain and their domain.
In addition to user authentication issues, the broken/dropped trust will also interrupt a few farm services you may have configured with this distant site.
1. Imports of AD user object data for profiles (profile imports)
2. Crawls/Indexing of sources located at this distant site
3. Assigning security principles (permissions) for users of the distant domain.
Be kind, be safe and have an outstanding day!
-Bill Beehner