You can test the block's effectiveness from the command line.
: If the IP address of your license server changes, the hardcoded entry in the hosts file will prevent SOLIDWORKS from launching until the file is manually updated.
SOLIDWORKS installation sometimes requires managing how the software communicates with license servers or activation servers, particularly in complex network environments, offline setups, or specific enterprise deployments. One powerful technique to control this communication is by editing the Windows to block specific domains.
The exact domains change over time and depend on your SolidWorks version. Network monitoring is needed to find all current endpoints.
Open the Windows Command Prompt by typing cmd in the Start menu. solidworks host file block install
in the Installation Manager (which often looks like a block), it is usually caused by Windows blocking extracted HTML files. : Navigate to \sldim\lang\english\HTML\ in your installation folder. Right-click frameset.html Properties , and click if the button is visible. MLC CAD Systems Summary Table: Resolution Methods Potential Cause Primary Fix Server Connection Failed DNS resolution failure Add IP/Hostname to Hosts file Blank Install Screen Windows security blocking HTML frameset.html in properties Multi-site PDM Issues Cross-domain communication Standardize name resolution in Hosts file
If cleaning the hosts file does not completely restore functionality, consider the following complementary troubleshooting steps: Check Third-Party Firewalls
SolidWorks relies heavily on network communication for activation, licensing, and installation verification. When a system cannot connect to the official Dassault Systèmes servers, it frequently points to a modified Windows hosts file. System administrators or security software often modify this file to block outbound connections, which accidentally prevents SolidWorks from installing or updating properly.
The SolidWorks Installation Manager and the SolidWorks Activation Wizard require constant communication with corporate servers. During a standard installation or modification, the software connects to several endpoints to perform critical tasks: You can test the block's effectiveness from the command line
Some users attempt to block SolidWorks from reaching its official activation or update servers by redirecting those domain names to an invalid IP address, such as 127.0.0.1 (localhost) or 0.0.0.0 . This is sometimes used in unofficial installation guides to prevent the software from verifying license keys against Dassault Systèmes' databases.
🛠️ Troubleshooting: SOLIDWORKS Installation Blocked by Hosts File
: Sometimes, organizational firewalls or proxy settings interfere with the SOLIDWORKS Installation Manager's ability to verify serial numbers or download files. Adding specific block or redirect rules can occasionally stabilize these connections. Why Block or Redirect During Install?
), you prevent your computer from establishing a connection with them. One powerful technique to control this communication is
127.0.0.1 crashdump.solidworks.com 127.0.0.1 performance.solidworks.com 127.0.0.1 usage.solidworks.com 127.0.0.1 customerstats.solidworks.com 127.0.0.1 analytics.solidworks.com
Some advanced network deployments also block swym.3ds.com (SolidWorks Community) and platform.3ds.com (3DEXPERIENCE platform integration).
A generic error message stating that the Installation Manager cannot connect to the server to verify your serial number.