Configuring DNS lookup time out period How to configure the DNS lookup time out settings To change the DNS lookup timeout settings, the registry must be accessed. To change the DNS lookup time out setting, follow the instructions below: WARNING!!
Incorrectly editing the registry can damage the server, please be sure you know what you are doing

1. Click on the start button
2. Select the run option
3. Type regedit, the registry editor will open
4. Select the HKEY_LOCAL_MACHINE key
5. Select the SYSTEM
6. Select CurrentControlSet
7. Select Services
8. Select SMTPRA
9. Select Parameters
10. Right click on the right pane and select NEW
11. Select DWORD Value
12. Right click on the new entry and select RENAME
13. Rename the entry to AsyncDnsTimeout1
14. Double click on the new entry AsyncDnsTimeout1
15. Select decimal
16. Enter a value in seconds, this parameter is an inactivity timeout in seconds, for example default is 180 for a 3 minutes timeout
17. Close the Registry editor