I worked out the cipher, and the message revealed itself:
Sophia explained that she had been tracking a group of rogue hackers, using the K7 Total Security software to stay one step ahead. She had hidden the laptop in my attic, knowing that it would be discovered eventually. k7-total-security-download-for-windows-10-get-into-pc
I was both intrigued and skeptical. What secrets could be hidden within this old laptop? I decided to do some research on K7 Total Security and its possible connections to the mysterious message. I worked out the cipher, and the message
"Meet me at the old clock tower at midnight. Come alone." I worked out the cipher