If your hosts file contains entries that redirect these specific SolidWorks domains to local addresses (like 127.0.0.1 or 0.0.0.0 ), the installer cannot reach the activation servers. This intentional or accidental blocking triggers immediate installation and licensing errors. Common Symptoms
If you manage a (on a dedicated server), the process changes slightly.
Paste the following file path into the address bar at the top of the open window: C:\Windows\System32\drivers\etc Press .
Newer versions of SolidWorks (2022 onward) have hard-coded fallbacks that detect hosts file redirection and refuse to proceed. Solution: You must either: solidworks host file block install
After editing the file, you must clear your computer's temporary network memory so it recognizes the changes immediately.
Read your SolidWorks EULA (End User License Agreement). Most clauses state:
At the bottom of the file, add the following lines to block connectivity to SOLIDWORKS activation servers (using 0.0.0.0 or 127.0.0.1 ensures the connection fails): If your hosts file contains entries that redirect
: Uncheck "Prevent any program from modifying the HOSTs file". : Go to Advanced Settings and uncheck "Lock Hosts File". Check File Attributes : Ensure the hosts file itself is not set to "Read-only". Navigate to C:\Windows\System32\drivers\etc Right-click the file and select Properties Run as Administrator
When attempting to activate the product post-install, the system throws a communication error, often indicating that the activation server cannot be reached. Step-by-Step Guide to Fix Hosts File Blocks
The process is nearly identical across all modern Windows versions. You will need an administrator account. Paste the following file path into the address
Scroll to the bottom of the file, past any lines starting with # . Add a new line for each address you want to block. : [IP Address] [Hostname]
), you prevent your computer from establishing a connection with them.
: Uncheck "Prevent any program from modifying the HOSTs file". ZoneAlarm : In Advanced Settings, uncheck "Lock Hosts File".
For admins running the license manager on Ubuntu/CentOS: