Solidworks Host File Block
Legitimate SolidWorks licenses connect to Dassault Systèmes’ activation servers to verify your subscription. However, a "cracked" or "patched" version of SolidWorks often comes with instructions to modify the HOSTS file. The goal is to block telemetry and license verification.
Typically, a user adds lines such as:
127.0.0.1 localhost
127.0.0.1 solidworks.com
127.0.0.1 licensing.solidworks.com
127.0.0.1 dsxclient.3ds.com
127.0.0.1 3ds.com
By doing this, whenever the pirated SolidWorks software tries to "phone home" to check if the license key is valid, the request hits a wall (your local computer) and fails. The software then stays in an "offline" or "activated" state indefinitely.
The vast majority of searches for "SolidWorks host file block" originate from users attempting to use pirated versions of SolidWorks. Here is why the hosts file is the weapon of choice for crackers:
1. Preventing Online Activation Checks Legitimate SolidWorks checks in with Dassault’s servers periodically. If a pirated key generator (keygen) was used, the software will eventually fail the online check and revert to "0 days remaining." By blocking the domain, the software cannot verify that the key is fake.
2. Disabling "Phantom" License Manager Calls
Even after uninstalling, SolidWorks leaves background services (like SolidWorks Licensing Service). These services attempt to send telemetry. The hosts file stops these background processes.
3. Stopping Automatic Updates Some users (even legitimate ones) block update servers to prevent a new version from downloading, as major updates can sometimes break existing workflows or custom macros.
The search term "Solidworks Host File Block" represents a bygone era of software piracy. In 2025, relying on a text file to block enterprise-grade licensing servers is like using a paper umbrella in a hurricane.
While it is technically possible to add entries like 127.0.0.1 licensing.solidworks.com, modern software will either crash, lock you out after 30 days, or silently report you to the license server via hard-coded IPs that ignore your HOSTS file.
The Bottom Line: If you need SolidWorks, pay for it. The subscription includes cloud services, simulation tools, and technical support. The cost of a stolen license—whether via ransomware, legal fines, or lost productivity—is infinitely higher than the retail price. Do not risk your computer or your career for a text file hack that no longer works.
Have a legitimate issue with your HOSTS file blocking your license? Contact your VAR (Value Added Reseller) for a remote fix.
In SOLIDWORKS, a "Host File Block" typically refers to a critical diagnostic workaround involving the modification of the Windows hosts file to resolve connectivity or performance issues between a workstation and a SOLIDWORKS PDM server. This technical intervention is primarily used when Domain Name System (DNS) failures prevent a computer from correctly translating a server's name into its IP address, causing the PDM client to hang or fail. Why the Host File is Blocked or Modified
The Windows hosts file serves as a local "address book" that the operating system checks before reaching out to external DNS servers. In a SOLIDWORKS environment, this file is used to:
Resolve Connection Lag: High latency in DNS resolution can cause massive slowdowns when opening or saving files in PDM. Manually mapping the server IP to its name in the hosts file bypasses this delay.
Bypass DNS Failures: If the PDM Archive or Database server cannot be found by its name, adding it to the hosts file ensures the client connects directly to the correct IP.
Identify Security Blocks: Antivirus programs (like SentinelOne, ZoneAlarm, or Webroot) often "block" the ability to write to the hosts file to prevent malware from redirecting traffic. These blocks must be temporarily disabled to apply the SOLIDWORKS fix. How to Configure the SOLIDWORKS PDM Host File
To implement this workaround, follow these steps to ensure the file is correctly updated and not being blocked by system permissions:
Launch Notepad as Administrator: Navigate to the Start menu, search for Notepad, right-click it, and select Run as Administrator. Open the Hosts File: 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 to see the hosts file (it has no extension).
Add Server Entries: On a new line at the bottom of the file, enter the server's IP address, followed by a tab or space, and then the server name. Example: 192.168.1.100 PDM-SERVER-01
Save and Verify: Save the file. If Windows denies saving, right-click the hosts file in File Explorer, select Properties, and ensure Read-only is unchecked. Troubleshooting Common Blocks
If you are unable to save the changes or the fix doesn't work, consider these common "blocks":
Antivirus Interference: Check your security software settings. For instance, in Webroot, you may need to uncheck "Prevent any program from modifying the HOSTs file".
Read-Only Attributes: Ensure the file is not locked by the system or another open application.
DNS Flush: After saving, open a Command Prompt and type ipconfig /flushdns to ensure the system recognizes the new local mapping.
Note: This modification is intended as a temporary diagnostic tool or a short-term workaround. For long-term stability, it is recommended to work with your IT department to resolve the underlying DNS issues within the network infrastructure.
Users often modify the Windows hosts file to prevent SolidWorks from communicating with its home servers. This is sometimes used for privacy or to manage software activation locally.
The Logic: By mapping a software's activation or telemetry URL to a "dead" IP address like 0.0.0.0 or 127.0.0.1, you effectively cut off the application's ability to reach that site.
Alternative Method: Experts often recommend using the Windows Defender Firewall for this instead, as it is easier to manage and less likely to be bypassed by modern Windows security features. 2. Resolving PDM Connectivity (The "Positive" Block)
In a professional setting, editing the hosts file is a common workaround when your computer cannot "find" the server hosting your SOLIDWORKS PDM (Product Data Management) vault.
The Issue: If your DNS (Domain Name System) fails to translate a server name into an IP address, PDM will fail to connect.
The Fix: Adding a manual entry to the hosts file ensures your machine always knows exactly where the server is located. How to Edit the Hosts File
If you need to perform either of these actions, the process is as follows: Solidworks Host File Block
Open Notepad as Administrator: Search for Notepad in the Start Menu, right-click it, and select Run as Administrator.
Navigate to the File: Go to File > Open and paste this path: C:\Windows\System32\drivers\etc\. Change the file type dropdown from "Text Documents (.txt)" to **"All Files (.*)"** to see the hosts file. Add Your Entry: To Block: Add a line like 0.0.0.0 license.solidworks.com.
To Connect (PDM): Add a line with the server IP followed by the name, e.g., 192.168.1.100 PDM-SERVER.
Save and Close: Save the file. You may need to restart your browser or SolidWorks for the changes to take effect. 3. SolidWorks "Blocks" (Internal CAD Feature)
It is worth noting that in SolidWorks, a "Block" is also a standard CAD feature used to group sketch entities.
block linked to file - best way to edit the block? | SOLIDWORKS Forums
In SOLIDWORKS PDM environments, the local Windows hosts file is used as a temporary workaround for DNS (Domain Name System) issues.
Bypassing DNS: If a client machine can "ping" a PDM server's IP address but cannot find it by name, the hosts file can manually map the name to the IP.
Blocking Connections: Conversely, entries in this file can be used to intentionally block communication with specific servers by mapping them to a non-existent or local IP address. 2. How to Edit the Hosts File
Modifying this file requires administrative privileges and careful formatting.
Run Notepad as Admin: Search for Notepad, right-click it, and select Run as Administrator.
Open the File: Navigate to C:\Windows\System32\drivers\etc. Change the file type filter to All Files to see the hosts file.
Add Entries: At the bottom of the file, add the IP address, a tab space, and the server name. Example: 192.168.1.100 PDMSERVER.
Flush DNS: After saving, open the Command Prompt and type ipconfig /flushdns to apply the changes. 3. Common "Blocks" and Issues
Antivirus Interference: Security programs like SentinelOne, ZoneAlarm, or Webroot often "lock" the hosts file. This can cause SOLIDWORKS installation errors because the installer cannot write necessary entries to the file.
Installation Failures: If the Windows built-in tools block downloaded .html files in the installation set, the SOLIDWORKS Installation Manager may fail. You must right-click the files and select Unblock in the properties menu.
Long-Term Risks: Using a local hosts file for a long period is discouraged, as it can lead to connection instability if the server's IP address eventually changes. 4. Blocking Log-ins (Administrative)
If your goal is to prevent users from accessing a vault for maintenance, administrators can use the SOLIDWORKS PDM Administration tool. Right-click the Vault > Properties > Block Log-ins.
This prevents new connections until Permit Log-ins is selected.
To better understand how to manage files and connectivity in SOLIDWORKS, these videos provide walkthroughs on fixing references and server communication: How to Fix SOLIDWORKS File References Hawk Ridge Systems
In SOLIDWORKS, there isn't a native "Host File Block" feature. However, modifying the Windows hosts file
is a common administrative workaround to resolve server connectivity issues or block specific traffic for licensing and PDM (Product Data Management) systems. Modifying the Windows Hosts File
The Windows hosts file acts as a local DNS override. To modify it for SOLIDWORKS server resolution: Run Notepad as Administrator
: Search for Notepad in the Start menu, right-click it, and select Run as Administrator Open the Hosts File : In Notepad, go to File > Open and navigate to: C:\Windows\System32\drivers\etc\ Note: Change the file type filter to **All Files ( )** to see the "hosts" file. Add Server Entries : At the bottom of the file (on a new line without a ), add the IP address, a tab/space, and the server name. 192.168.1.100 MyPDMServer Save and Flush DNS
: Save the file. To ensure the change takes effect immediately, open a Command Prompt and type ipconfig /flushdns MLC CAD Systems Common Issues & Troubleshooting
If you are unable to save changes or the feature is "blocked," check the following: Write Access Blocked
: Antivirus software (such as Webroot, ZoneAlarm, or SentinelOne) may actively block any application from writing to the hosts file. You must uncheck settings like "Prevent any program from modifying the HOSTs file" in your security software. Read-Only Attribute : Right-click the hosts file, select Properties , and ensure the box is unchecked. Administrative Permissions
: Installation or modification of licensing services requires local administrative rights to write to the Windows registry. Related SOLIDWORKS "Block" Features
If you are looking for specific CAD or PDM features named "Block": File Locations Options - 2023 - SOLIDWORKS Design Help
In the context of SOLIDWORKS, "blocking" in the hosts file is typically a troubleshooting technique used to bypass DNS issues by explicitly mapping server names to IP addresses. Conversely, the hosts file can also be used to intentionally block network communication for licensing or update purposes. Purpose of Modifying the Hosts File
DNS Resolution (Workaround): Often used as a temporary fix for SOLIDWORKS PDM connection issues. It allows the client machine to resolve server names directly to an IPv4 address, bypassing problematic DNS lookups.
Intentional Blocking: By mapping a hostname to an invalid IP address like 0.0.0.0, you can prevent the software from reaching specific domains, such as update or licensing servers. By doing this, whenever the pirated SolidWorks software
Security & Multi-Site Setup: Essential for servers to communicate across different network domains or WANs by defining remote server IPs. How to Block or Map Hostnames
The Windows hosts file is located at: C:\Windows\System32\drivers\etc\hosts.
Open as Admin: You must run Notepad as an administrator to save changes. Add Entries:
To Allow (Map): Add a line with the [IP Address] [Tab] [Server Name]. To Block: Add a line with 0.0.0.0 [Domain Name].
Flush DNS: After saving, open the Command Prompt and run ipconfig /flushdns to apply changes immediately. Common Issues & Conflicts
Antivirus Interference: Security software like SentinelOne, ZoneAlarm, or Webroot may prevent modifications to the hosts file as a security measure.
Read-Only Status: Ensure the file attributes are not set to "Read-only" in the file properties.
Incorrect Format: The file must not have an extension (e.g., hosts.txt will not work).
For a visual walkthrough on how to safely edit these system files to block or map addresses, watch this guide:
SolidWorks relies on a licensing system that often needs to "phone home" to a server. Sometimes, users or third-party scripts modify the Windows Hosts file to block these connections, which can lead to activation errors, crashes, or "License client lost" messages. The Day the Design Office Stood Still
Alex sat at his desk, ready to finalize the assembly for the new drone prototype. He double-clicked the SolidWorks icon. He waited. Instead of the familiar splash screen, a cold, grey box appeared:"Could not obtain a license for SOLIDWORKS. System Clock Check Failed or Licensing Service is unavailable."
Alex knew his internet was fine. He knew the company server was up. He remembered a "performance hack" he had found on a forum the night before—a script that supposedly sped up load times by blocking "unnecessary background pings." The Hidden Gatekeeper
What Alex hadn't realized was that the script had edited his Hosts file. This file is like a private phone book for your computer; it tells Windows exactly where to find specific internet addresses before it even asks a DNS server.
By adding lines like 127.0.0.1 ://solidworks.com, the script had told Alex’s computer that the SolidWorks licensing server was actually inside his own machine. When SolidWorks tried to verify his seat, it hit a digital brick wall. The Restoration To fix it, Alex had to perform a bit of "digital surgery":
Locate the File: He navigated to C:\Windows\System32\drivers\etc.
Gain Permission: He opened Notepad as an Administrator, then dragged the hosts file into the window.
The Purge: He looked for any lines containing "SolidWorks" or "Flexnet." He saw a dozen entries redirecting traffic to 0.0.0.0 or 127.0.0.1.
Clean Slate: He deleted those lines, saved the file, and restarted his computer. The Lesson
When Alex restarted SolidWorks, the software reached out, found the genuine server, and blossomed into life. He learned that while "blocking pings" might sound like a shortcut to speed, it usually just cuts the lifeline the software needs to function. 🛠️ Common Signs Your Hosts File is Blocked
Activation Errors: "Failed to connect to the activation server."
Startup Hangs: The splash screen stays visible for minutes before failing. FlexNet Errors: Error codes like -15, 10 or -8, 544. 💡 Pro-Tips for Troubleshooting
Check for "Read-Only": Right-click the hosts file > Properties. Ensure "Read-only" is unchecked before saving.
Anti-Virus Interaction: Sometimes, your AV software will "protect" the hosts file and revert your changes. Disable it temporarily while editing.
Standard DNS: If the file is clean but it still fails, try flushing your DNS cache by typing ipconfig /flushdns in the Command Prompt.
Walk through the specific license server port numbers (25734/25735) to check your firewall? Troubleshoot a specific error code you are seeing?
Troubleshooting SOLIDWORKS Connection: The "Host File" Fix If you have ever been met with a "Could not access the item in the database" error or found your SOLIDWORKS PDM client unable to "see" the server, you know how frustrating it can be. While it often looks like a complex networking failure, the solution is frequently found in a simple text file: the Windows Hosts file. What is the Hosts File?
Think of the Hosts file as your computer's personal address book. Before your computer asks a Domain Name System (DNS) to find a server's IP address, it checks this local file first. If the DNS is misconfigured or blocking the connection, you can manually map the SOLIDWORKS server name to its IP address here to bypass the roadblock. How to Fix the "Host File Block"
Follow these steps to manually add your server and restore your SOLIDWORKS connection:
Open Notepad as Administrator: Search for Notepad in your Start menu, right-click it, and select Run as Administrator. (This is required to save changes to system files).
Navigate to the File: In Notepad, go to File > Open. Navigate to the following path:C:\Windows\System32\drivers\etc\
Reveal the Hosts File: By default, Notepad only looks for .txt files. Change the file type dropdown in the bottom right from Text Documents (*.txt) to All Files (.) to see the "hosts" file.
Add the Server Entry: Scroll to the bottom of the file. On a new line, type your server's IP address, press the TAB key, and then type your server name. Example: 192.168.1.100 MyPDMServer Save and Exit: Save the file (Ctrl + S) and close Notepad. Why This Works Common Issues with Host File Block
By explicitly linking the name and IP, you eliminate the "guesswork" for your computer. This is especially helpful in WAN environments or when local firewalls/DNS settings are being overprotective and "blocking" the standard handshake between your machine and the Archive or Database server. Pro-Tips for Success
Permissions: Ensure you have local Windows Administrator credentials, or you won't be able to save your changes.
Static IPs: This fix works best if your server has a static IP. If the server's IP changes, you will need to update this file again.
Check Your Ports: If the Hosts file doesn't fix it, ensure your firewall isn't blocking the specific ports SOLIDWORKS needs, such as 3030 (Archive), 1433 (SQL), or 25734/25735 (Licensing).
For more advanced troubleshooting, you can always check the Official SOLIDWORKS Support pages or consult with a technical partner like GoEngineer or MLC CAD Systems.
The "SolidWorks Hosts File" Trick: Solving Connection Lag and License Gremlins
If you’ve ever sat staring at the SolidWorks splash screen while it hangs on "Initializing License," you know the frustration. Sometimes, the software feels like it’s trying to call home to a server that doesn't exist, or it’s getting tripped up by a DNS loop. Hosts File Block
. While it sounds like a "hacker" move, it's actually a common troubleshooting step for CAD administrators to stabilize network licensing and prevent unwanted background "phone-home" lag. What is the Hosts File?
Think of your Windows Hosts file as a private address book for your computer. Before your PC asks a DNS server (the internet's phone book) where a website or server is, it checks this local file first. If you put an entry in there, your computer takes it as gospel. Why "Block" or Redirect for SolidWorks?
There are two main reasons CAD power users touch the hosts file: Server Redirection: If your SolidWorks License Manager is on a server named CAD-SERVER-01
, but your network is having trouble resolving that name, you can "hardcode" the IP address in your hosts file. This bypasses the network lag and connects you instantly. Blocking "Telemetry" or Update Checks: Sometimes, background processes (like sldworks.exe
) try to reach out to external URLs for updates or usage tracking. In high-security environments or systems with strict firewalls, these attempts can cause the software to "stutter." By "blocking" these URLs (redirecting them to ), you keep the traffic local and the software snappy. How to Do It (The Safe Way) To edit the file, you’ll need to find it at: C:\Windows\System32\drivers\etc\hosts The Steps: Run as Admin:
You must open Notepad (or your editor of choice) as an Administrator, or you won't be able to save your changes. The Syntax: To block a specific address, you map it to . For example: 127.0.0.1 im-a-server-causing-lag.solidworks.com Save and Flush: Save the file, then open your Command Prompt and type ipconfig /flushdns to make the changes active immediately. When Should You Use This?
This isn't a "set it and forget it" fix for everyone. You should consider a hosts file tweak if: Your license takes more than 30 seconds to pull.
You are working in a "dark site" (no internet) and want to stop the software from timing out on web-based pings.
You’ve migrated your license server and don't want to wait for DNS propagation across the office. A Quick Warning
The hosts file is powerful. If you accidentally block a legitimate activation server, you might find yourself locked out of your seat entirely. Always make a backup of your original hosts file before you start tinkering.
Have you used a hosts file tweak to speed up your SolidWorks workflow?
Drop a comment and let us know which addresses you found were the biggest culprits for lag! Need more help with PDM or Vault views? Check out the official SOLIDWORKS PDM Help for server setup tips, or learn more about clearing local caches MLC CAD Systems specific IP addresses to use for a SolidWorks license server redirect?
Solidworks Host File Block: A Comprehensive Review
Introduction
Solidworks, a popular computer-aided design (CAD) software, relies on a complex network of files and configurations to function properly. One crucial aspect of Solidworks administration is managing the host file block, which can significantly impact performance, collaboration, and data integrity. In this review, we'll delve into the concept of the Solidworks host file block, its implications, and best practices for management.
What is a Host File Block in Solidworks?
In Solidworks, a host file block is a mechanism that prevents multiple users from accessing and editing the same file simultaneously. When a user opens a file, Solidworks creates a lock on the file, preventing other users from modifying it until the file is closed or checked back into the vault. This feature ensures data integrity and prevents accidental overwriting of changes.
Key Benefits of Host File Block
Common Issues with Host File Block
Best Practices for Managing Host File Block
Conclusion
The Solidworks host file block is a critical feature that ensures data integrity and prevents conflicts when multiple users access and edit files. While it offers several benefits, it also requires careful administration and management to prevent performance issues and file lock conflicts. By implementing best practices and understanding the implications of host file blocking, Solidworks administrators can optimize their workflow, promote collaboration, and ensure data integrity.
Rating: 4.5/5
The Solidworks host file block is an essential feature for managing file access and ensuring data integrity. While it requires careful administration, its benefits far outweigh its drawbacks. With proper management and configuration, the host file block can significantly improve collaboration, productivity, and data security in Solidworks environments.
Scroll to the bottom of the file. Add the following lines (these are the most historically used domains):
# SolidWorks License Block
0.0.0.0 solidworks.com
0.0.0.0 license.solidworks.com
0.0.0.0 licenses.solidworks.com
0.0.0.0 register.solidworks.com
0.0.0.0 activation.solidworks.com
0.0.0.0 geometricglobal.com
0.0.0.0 pub.solidworks.com
0.0.0.0 sw.global.plm.automation.siemens.com
0.0.0.0 lmt.solidworks.com
0.0.0.0 solidworkslicense.com
0.0.0.0 training.solidworks.com