The Windows hosts file is a local plain-text file used by the operating system to map hostnames (like myserver.com) to specific IP addresses. It is located at:C:\Windows\System32\drivers\etc\hosts
When your computer tries to connect to a server, it checks this local file first before asking a Domain Name System (DNS). 1. Using a Hosts File Block for Troubleshooting
In many professional environments, SolidWorks PDM or network licenses fail because the client computer cannot find the server by its name. A "host file block" (or more accurately, a manual entry) can bypass these DNS errors.
The Issue: A client can "ping" the server's IP address but not its name, leading to connection timeouts.
The Fix: You can manually map the server name to its IP address to ensure a direct connection. Step-by-Step Configuration: Open Notepad as an Administrator. Navigate to C:\Windows\System32\drivers\etc\.
Open the hosts file (you may need to change the file type to "All Files").
Add a new line at the bottom: [Server IP Address] [Server Name]. Example: 192.168.1.50 MyArchiveServer.
Save the file and run ipconfig /flushdns in the Command Prompt to apply the changes. 2. Blocking SolidWorks from the Internet
Some users intentionally block SolidWorks domains in the hosts file to prevent the software from contacting the manufacturer's activation or telemetry servers. This is often done by mapping SolidWorks URLs to the loopback address (127.0.0.1 or 0.0.0.0), which effectively kills the connection. Common Domains Blocked: install.solidworks.com api.solidworks.com www.solidworks.com Risks of This Method: Solidworks Host File Block
Activation Failures: You will be unable to activate, reactivate, or transfer your license.
Update Issues: The SolidWorks Installation Manager will fail to check for updates or download required files.
Feature Loss: Cloud-integrated features or the 3DEXPERIENCE platform may stop working. 3. Resolving Unintended Blocks
If you are receiving "Cannot find license file" or "License server down" errors (Error -15,10,10061), a rogue entry in your hosts file might be the culprit.
A "Solidworks Host File Block" usually refers to modifying the Windows
file to prevent the SolidWorks application from communicating with validation or telemetry servers. This is often done to bypass license checks or stop unwanted data collection. 1. Locating the Hosts File
The hosts file is a system file that maps hostnames to IP addresses. C:\Windows\System32\drivers\etc (it has no file extension). 2. Editing the File (Requires Admin Rights)
You cannot save changes to this file without administrative privileges. Start Menu , right-click it, and select Run as Administrator In Notepad, go to File > Open Paste the path C:\Windows\System32\drivers\etc into the address bar. The Windows hosts file is a local plain-text
Change the file type filter (bottom right) from "Text Documents ( .txt)" to **"All Files ( Select the file and click 3. Adding the Blocks
To block SolidWorks from reaching specific servers, you map the server's domain name to your local machine (IP ). Common addresses targeted include: 127.0.0.1 activation.solidworks.com 127.0.0.1 im-node1.solidworks.com 127.0.0.1 im-node2.solidworks.com 127.0.0.1 sldworks-entitlements.solidworks.com
Note: Adding these lines ensures that whenever SolidWorks tries to "call home," the request is rerouted back to your own computer and fails. 4. Verifying the Block Command Prompt in the Start Menu). ping activation.solidworks.com If the block is successful, you should see it pinging rather than an external IP address. 5. Complementary Firewall Blocks
For a "complete" block, users often supplement host file edits with Outbound Rules Windows Defender Firewall Firewall & network protection > Advanced settings Outbound Rules > New Rule and browse to the SLDWORKS.exe file (usually in C:\Program Files\SOLIDWORKS Corp\SOLIDWORKS Block the connection and apply it to Domain, Private, and Public profiles.
Modifying these files to bypass licensing is a violation of the software's Terms of Service. For official support or license management, refer to the SolidWorks SolidNetWork License (SNL) Manager documentation. If you'd like, let me know: Are you trying to block activation Are you using a standalone
Disclaimer: This report is for educational and informational purposes regarding software network behavior and system administration. Circumventing paid software licenses (piracy) is illegal and violates software terms of service. This guide does not promote or instruct how to use unlicensed software.
Locate the Hosts file:
C:\Windows\System32\drivers\etc\hosts
Open as Administrator:
etc → select "All Files" (.) → open hosts.Add blocking entries: Append lines at the end. Example:
# SolidWorks blocking
127.0.0.1 activation.solidworks.com
127.0.0.1 licensing.solidworks.com
Save the file (no extension).
Flush DNS cache (to ensure immediate effect):
ipconfig /flushdns
Restart SolidWorks licensing services (optional but recommended):
net stop "SolidWorks Licensing Service"
net start "SolidWorks Licensing Service"
If you are using a network license crack, the software sends a "heartbeat" every 15 minutes. The hosts file blocks the license server but not the heartbeat validation. Eventually, the local client realizes it cannot talk to the license manager and shuts down.
There are two primary reasons network administrators or users implement this block:
While editing the hosts file is not a virus, the act of doing it for pirated software opens dangerous doors.
Legitimate users get security patches. If you block the host file, you block those patches. Vulnerabilities in older versions of SolidWorks have been used as entry points for corporate espionage. Troubleshooting Common Issues Procedure