enys1960 wrote:
My Macbook Pro came with pre-installed SW so I don't have any physical installation disc.
Every Mac sold has the OS preinstalled, and every Mac comes with the installation disk set. If you purchased your MacBook Pro new, then unless Apple's factory made a packing mistake, the MBP came with a disk set. Look more carefully through the packaging; the disks should be in a white sleeve/thin box along with the small "getting started" manual.
If you purchased the Mac used or from a dealer and it was opened stock, contact the seller and demand a disk set. If you can't get one from the seller, or you lost or inadvertently threw away the disk set, call Apple tech support and they can sell you a disk set for a reasonable fee. You really need to have an installation disk set, for many reasons.
Regards.