UserLock Documentation
UserLock Documentation
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HTF002 - Allow the ICMP protocol (ping)

Error message

Unable to ping the computer [Machine Name].

How to fix

  1. Check that the machine account still exists in Active Directory.
  2. Check that the machine is online.
  3. Check that a firewall between the server and the machine isn't blocking the ICMP protocol (ping).
    UserLock communications require the ICMP and the Microsoft File and Printer Sharing protocols. The firewall on the server hosting UserLock and on all machines protected by UserLock must authorize these two protocols.
    In the Windows Firewall, click on 'Allow an app or feature through Windows Firewall'.

    Enable 'File and Printer Sharing' for the domain by checking its corresponding box. Click on 'OK'. Both required protocols will be authorized.

    For more security, we suggest you enable these two protocols through a Microsoft Group Policy. This will also allow you to specify IP restriction on the UserLock server IP as only allowed source.

  4. Try to deploy the agent on the target machine again.

To apply requirements on UserLock Server and protected machines through Group Policies (recommended): see this page.