Hi everyone,

Lately, we have had some support cases with the same root cause, namely a delay in opening software using FLEX component (Graitec and Autodesk products) or delay in opening license tools.

For example, during a training session: When AD was opening it took a long time to start up, but just running in processes with nothing on the display. It also happened when opening AutoCAD, it was a delay of about 1 to 2 minutes. You couldn't see what was happening with AD but with AutoCAD you could see it was a delay when "Checking Licence" so I think both are related.

The delay is caused by a routine check of the local network performed by the FLEX protection component, an issue known and treated by FLEX.

The solution is to block the IP class from the firewall (firewall must be enabled). Create an outbound rule on the local firewall that blocks connections to Below are instructions for adding this rule to the Windows Firewall:

Note: For 3rd party firewalls, consult your firewall documentation to add an outbound rule that blocks connections to

1. Make sure that the Firewall is enabled. Open Windows Control Panel and go to “System and Security” and then “Windows Firewall“.

2. Click “Advanced settings” on the left panel to open “Windows Firewall with Advanced Security”.

3. Single click the “Outbound Rules” tree item on the left panel, then choose “New Rule…” on right panel to create a new firewall. Select “Custom” and click “Next”.

4. Select “All Programs” and click the “Next” button. Skip the next page by clicking the “Next” button again.

5. Select “These IP addresses” under “Remote IP addresses”. Click on “Add…” and enter the IP address in the designated space. Click OK and then click “Next”.

6. Select “Block the connection” and click on “Next” to proceed.

7. Click “Next” again to include “Domain”, “Private” and “Public”.

8. Windows will ask you to write a description for the firewall rule. After entering at least the name, click on the “Next” button. Click “Finish” to create and implement this rule that will block the desired IP address.

Note: FLEX states in “FlexNet Publisher 2016 R1 Service Pack 1 (”: on Windows, in the presence of some anti-virus systems such as Kaspersky or AVG, queries to link-local addresses (169.254.*.*) can result in a WSACleanup delay.

This issue is also documented in the Installation Guide for GRAITEC software.