If Photoshop CC 2017 won't open on a newer OS, try running it in : Right-click the Photoshop icon. Select Properties > Compatibility .
Even for CC 2017, Adobe quickly released updates (18.0.1, 18.1.2) that changed the file signatures. Patch tools became outdated within weeks.
Earlier patches like APSB17-12 resolved memory corruption vulnerabilities when parsing PCX files [21].
If you own a valid license for Photoshop CC 2017 but lost access, contact Adobe Support for recovery options. I’m happy to help with legitimate software setup, troubleshooting, or alternative tool recommendations.