This is almost always a SQL issue. Run the "Aspen Properties Database Configuration" utility as an Administrator to re-link the databases.
: This is vital for the Aspen Properties database. Always run this setup as an administrator. 2. Optimized Installation Steps how to install aspen hysys v12 better
💡 Always run the installer as an Administrator . Even if your account has admin rights, right-clicking the Setup.exe and choosing "Run as Administrator" ensures the installer has the depth of permissions needed to write to the Windows Registry and System32 folders. This is almost always a SQL issue