https://support.eset.com/kb3005

Solution

After you have created your Mirror server, you must configure client workstations to access it for updates.

Configuring clients to access the Mirror server

1. Open the main program window by double-clicking the ESET icon  in your Windows notification area or by clicking Start → All Programs → ESET → ESET Endpoint Security or ESET Endpoint Antivirus.

2. Press the F5 key to display the Advanced Setup window. From the tree structure on the left, expand Update → General and then click Edit...

Figure 1-1
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3. To add your Mirror server as an update server, enter the server name or IP address in the following format: http://your_server_name:2221 or http://xxx.xxx.xxx.xxx:2221.

4. Click Add, and then click OK to return to the Advanced Setup window.

Figure 1-2

5. Make sure the Username and Password fields are blank and that the Mirror server name or address is visible. Click OK once more to save your settings and close the Advanced Setup window. The ESET client(s) you have just configured should now update successfully from the Mirror server.

Figure 1-3
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