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I want to get the group principal based on display name instead of SAMAccountname.

GroupPrincipal group = GroupPrincipal.FindByIdentity(ctx, "My Testing Group");

My Testing Group is display name while My_Testing_Group SamAccountName. Above statement returns null while below one works fine:

GroupPrincipal group = GroupPrincipal.FindByIdentity(ctx, "My_Testing_Group");

Please help.