Block Fix | Solidworks Host File

SolidWorks background processes (e.g., sldworks_fs.exe , SWLicensingService ) periodically check in with Dassault Systèmes’ activation servers. By editing the hosts file, you redirect those server names to a dead end (usually 127.0.0.1 – your own computer).

: In Notepad, go to File > Open . Navigate to C:\Windows\System32\drivers\etc\ . Change the file type filter in the bottom right from "Text Documents (*.txt)" to All Files .

: Search for Notepad in the Start Menu, right-click it, and select Run as Administrator . solidworks host file block fix

Inside Notepad, click on in the top menu bar, then click Open... (or press Ctrl + O ).

If Windows forces you to save the file as a .txt document or says "Access Denied," Notepad was not launched with full administrative rights. Close Notepad completely, re-verify you are using an admin account, and repeat Step One by explicitly choosing "Run as administrator." Antivirus Software Blocks the Change SolidWorks background processes (e

Select . Click Yes if the User Account Control (UAC) prompt appears. Step 2: Locate the Hosts File In Notepad, click File in the top menu, then click Open .

: If the SolidNetWork License Manager cannot reach the license server due to name resolution failure. server names for your office network to complete the file edit? Retired - SOLIDWORKS Forums Navigate to C:\Windows\System32\drivers\etc\

How to Fix SolidWorks Activation and Licensing Issues via the Hosts File

If SolidWorks fails to activate with a message about firewall issues, server unavailability, or "invalid license," it is likely a blocked connection.

Look for lines that contain terms related to SolidWorks, Dassault Systèmes, or FlexNet. Common examples include: 127.0.0.1 ://solidworks.com 127.0.0.1 ://dassaultsystemes.com 0.0.0.0 ://solidworks.com

Some modern endpoint protection software blocks unknown inbound and outbound license requests. Add exceptions to your antivirus software for the following primary executable files located in your SolidWorks installation directory: sldworks.exe lmgrd.exe sw_d.exe Conclusion