Do not reinstall Windows. Do not delete your project files. Follow this triage order (from least to most invasive) to resolve
Antivirus or firewall settings may be preventing Autodesk’s URLs from validating the license. Step-by-Step Fixes for 3ds Max 2023 1. Synchronize Your System Time There Is A Problem With The Software License 3ds Max 2023
Navigate to C:\Program Files (x86)\Common Files\Autodesk Shared\AdskLicensing . Run the uninstall.exe file as an administrator. Do not reinstall Windows