Getting Started with Simply Modbus Master 8.1.2: Licensing and Features

In demo mode, a startup window appears with a 15-second progress bar. You can press the ENTER KEY during this time to proceed to the main window. 2. Best Licensing Options

If you're looking for a license key, I recommend:

read and write requests (demo mode is limited to six requests per session) Simply Modbus Full technical support from the developer Simply Modbus Demo vs. Licensed Comparison

Most "license key generators" for industrial software contain trojans. Once installed on your engineering laptop, they can spread to PLCs or HMIs on your network.