If you suspect your hosts file is causing issues, follow these steps to clean it up or add necessary workarounds:
: Navigate to C:\Windows\System32\drivers\etc\ .
Select any lines containing these keywords and delete them entirely. Step 4: Save and Flush the DNS Cache Click File > Save (or press Ctrl + S ). Close Notepad.
The "solidworks host file block install" method is a classic, low-level networking trick that modifies how your PC looks up addresses. For versions of SOLIDWORKS (including 2025 and 2026), editing the C:\Windows\System32\drivers\etc\hosts file to redirect validation servers to 127.0.0.1 is often the first line of defense against license checks. However, because it requires specific permissions and is often locked by antivirus software, it should be paired with Firewall outbound rules for maximum effectiveness. Always ensure you have a legitimate license for the software you use in a professional environment. solidworks host file block install
This report outlines technical issues and resolutions related to the Windows "hosts" file and file blocking during SOLIDWORKS installations.
SolidWorks Host File Block Install: A Guide to Troubleshooting and Proper Licensing
This public link is valid for 7 days and shares a thread, including any personal information you added. This link or copies made by others cannot be deleted. If you share with third parties, their policies apply. Can’t copy the link right now. Try again later. Repairing an Installation - 2021 - SOLIDWORKS Design Help If you suspect your hosts file is causing
This priority gives you, the user, absolute control over name resolution for your machine. By adding a specific entry, you can tell your computer to look for the domain of a license server at a completely different address—such as your own loopback address ( 127.0.0.1 ). In the context of activation blocking, you are essentially tricking your computer into thinking the activation server is your own local machine, which doesn't know how to respond, thereby effectively "blocking" the connection.
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 hosts file is located in different directories depending on the operating system: Close Notepad
In Notepad, go to File > Open. Navigate to C:\Windows\System32\drivers\etc\ . Change the file type to "All Files" and open the hosts file. Add the Blocking Entries: Add the IP address
Right-click on the Notepad application from the search results and select . Click Yes if the User Account Control (UAC) prompt appears. Step 2: Locate and Open the Hosts File
Confirm the User Account Control (UAC) prompt if it appears. Step 2: Navigate to the Systems Folder Inside Notepad, click in the top menu and select Open .
: Fetching the actual installation files from global content delivery networks (CDNs).
EN 
EL