Can't place without losing styling

Hi

Using Indesign CS6 on Mac OS X Snow Leopard.

Don't know why can't place a simple .rtf file that have bold and italics styling without losing the original style.

On Place's RTF Import Options select "Preserve Styles and Formatting from Text and Tables" and don't works, original style is lost after placing.

Can't use via Indesign's "paste without formatting" because is DIMMED. Why?

How can import a simple rtf file without losing the original styling of bold and italics?

Thanks.

Tom

Note: Don't find the answer at this forum after searching.