private bool HasRights(FileSystemRights fileSystemRights_, string fileName_, bool isFile_)
    {
        bool hasRights = false;

        WindowsIdentity WinIdentity = System.Security.Principal.WindowsIdentity.GetCurrent();
        WindowsPrincipal WinPrincipal = new WindowsPrincipal(WinIdentity);

        AuthorizationRuleCollection arc = null;

        if (isFile_)
        {
            FileInfo fi = new FileInfo(@fileName_);
            arc = fi.GetAccessControl().GetAccessRules(true, true, typeof(NTAccount));
        }
        else
        {
            DirectoryInfo di = new DirectoryInfo(@fileName_);
            arc = di.GetAccessControl().GetAccessRules(true, true, typeof(NTAccount));
        }

        foreach (FileSystemAccessRule rule in arc)
        {
            if (WinPrincipal.IsInRole(rule.IdentityReference.Value))
            {
                if (((int)rule.FileSystemRights & (int)fileSystemRights_) > 0)
                {
                    if (rule.AccessControlType == AccessControlType.Allow)
                        hasRights = true;
                    else if (rule.AccessControlType == AccessControlType.Deny)
                    {
                        hasRights = false;
                        break;
                    }
                }
            }
        }

        return hasRights;
    }

The above code block is causing me problems. When the WinPrincipal.IsInRole(rule.IdentityReference.Value) is executed the following exception occurs:

"The trust relationship between the primary domain and the trusted domain failed.".

I'm very new to using identities, principles and such so I don't know what's the problem. I'm assuming it's with the use of NTAccount?

Thanks