Solidworks Host File Block Fix -
The Windows hosts file is a plain text file that maps hostnames to IP addresses. It is used to override DNS settings. Sometimes, security software, network policies, or previous installations of unauthorized software can add entries to this file that intentionally block access to specific websites—in this case, SolidWorks activation servers. When this happens, you might see errors like: "Cannot connect to the server" "License activation failed"
To resolve SOLIDWORKS connectivity issues, specifically when a client machine cannot communicate with the license or PDM server, modifying the Windows
By default, Notepad only displays .txt files, making the folder look empty. In the bottom-right corner of the Open dialog box, change the dropdown menu from to All Files ( . ) .
Paste the following path into the address bar at the top and hit Enter: C:\Windows\System32\drivers\etc solidworks host file block fix
Right-click the blocking rule and select or Delete .
The first step is to locate the file. It does not have a file extension. Open .
| | Solution | |-------------|---------------| | "Access Denied" when saving | You did not run Notepad as Administrator. | | Changes don't take effect | Windows DNS cache: Reboot or run ipconfig /flushdns . | | SolidWorks still activates | You missed a new server address. Use Wireshark to monitor SolidWorks outbound traffic. | | Internet is slow or broken | You accidentally blocked a critical domain (e.g., windows.com ). Remove bad lines. | | Antivirus restores old host file | Add C:\Windows\System32\drivers\etc\hosts to your antivirus exclusion list. | The Windows hosts file is a plain text
Select the file named (with no file extension) and click open.
If you receive an error that the hosts file is blocked or cannot be modified, check these settings:
Note: Ensure there is a space or a tab between the numbers and the text, and do not include any # symbols at the beginning of these lines, as # tells Windows to ignore the line. Step 4: Save and Close Click , then select Save (or press Ctrl + S ). Close Notepad. Step 5: Flush Your DNS Cache When this happens, you might see errors like:
"No internet connection detected" (when you clearly have one) Step 1: Locating the Windows Hosts File
By far the most common cause. If a computer previously hosted an unauthorized or cracked version of SolidWorks (such as those bundled with "SSQ" or "SolidSquad" activators), the crack script automatically modifies the Windows Hosts file. It does this deliberately to prevent the illegal software from "phoning home" to Dassault Systèmes and getting flagged. If you later try to install a legitimate, legal license on that same machine, the old blocks remain and break the official activation process. Step-by-Step Guide to Fix the SolidWorks Hosts File Block
: Adding entries to the hosts file "unblocks" communication by telling your PC exactly where to look for the license server when the network fails to do so. Blocking (Cracked Software) : In unofficial versions, users often add entries like 127.0.0.1 activation.solidworks.com
Dassault Systèmes (the maker of SolidWorks) has long since moved past simple host-file checks. Here is why the "fix" fails today:
The hosts file is a protected system file. You cannot edit it without administrative rights. Click the and type Notepad .
