This site is being deprecated.
Please see the official X‑Plane Support page for help.
I am not from Laminar Research; just a flight simmer.
The short quick answer is "yes you can".
I presume you are commenting about the official version of X-Plane from Laminar Research and not Steam version. They are not the same product. Steam is not sold by Laminar research.
I am a little confused in my interpretation of your opening comment and assume that you have purchased and loaded a disc version of X-Plane.
To get a replacement disc you need to make a direct contact with Laminar Research starting at firstname.lastname@example.org
This site is no longer being actively maintained.