Some third-party firewalls, antivirus suites, or malware removal tools automatically append corporate or activation domains to the hosts file to prevent data tracking.
Some SolidWorks network licenses rely on a "Heartbeat." If the software cannot ping the activation server every 30 to 90 days, it assumes the license is stolen and disables itself. Adding a block stops this remote kill-switch.
For network installations, ensure that the SolidWorks SolidNetWork License (SNL) Manager is properly configured. If the client machine cannot reach the host server, use the command prompt to ping the server name or IP address directly to verify network visibility. Clean Installation Environment solidworks host file block install
In temporary testing environments, you may not want to use a license seat.
Read your SolidWorks EULA (End User License Agreement). Most clauses state: Read your SolidWorks EULA (End User License Agreement)
I utilized the host file block method during a fresh install of SolidWorks 2024 on a high-security corporate network. The standard installation manager failed repeatedly at the "Initializing" stage due to firewall restrictions blocking callbacks to swdm.solidworks.com and activation.solidworks.com .
If it is not listed, click and browse to your SolidWorks installation source folder to add sldim.exe . Best Practices for a Smooth SolidWorks Installation display "License Error -15
Here is the catch: Even with a valid license, SolidWorks continuously attempts to reach specific telemetry and validation server addresses. If the software fails to validate a license (due to a firewall, DNS error, or server outage), it may revert to "Viewer Mode" or shut down completely after 30 days.
The software cached the old validation result. Fix:
This technical guide explains how the Windows Hosts file affects SolidWorks, why it blocks installations, and how to safely reset it to restore full functionality. Understanding the Hosts File and SolidWorks Activation
Modern versions of SOLIDWORKS (including 2024, 2025, and 2026) frequently attempt to reach out to Dassault Systèmes' activation and license validation servers. During a "cracked" or "offline" activation process, this validation needs to be prevented. If the software reaches the internet and fails to validate a serial number, it may revert to a trial mode, display "License Error -15,10,10061", or simply refuse to launch. Blocking via the hosts file ensures that while you maintain internet connectivity for other applications, SOLIDWORKS cannot check its license status externally.