| Gather Clues | |
| A. | Ask Questions. i. What were you doing when the problem occurred? ii. Have there been any recent changes to the network? |
| B. | Have the customer recreate the problem while you watch. While watching, check for obvious user errors (ID10T errors), such as Caps-Lock being on. |
| Possible Solutions | |
| A. | Faulty application software. Check app’s settings. Try reinstalling app. Check app manufacturer’s website. If it is a web browser, clear the cache & check the proxy settings. |
| B. | Misconfigured firewall. Disable Windows firewall. Check with admin of network firewall to see if workstation is being blocked. |
| C. | Invalid entry for destination name in \windows\system32\drivers\etc\hosts file. It normally should not be listed in this file at all. |
| D. | Insufficient rights to access service. Check with admin of service or the server itself to see if user has sufficient rights or their account has been disabled. |
| E. | User is using incorrect username and/or password. |
| F. | Malware infection. Scan system for malware infection using anti-malware software such as MalwareBytes. |
| If All Else Fails | |
| A. | Sniff the network with Wireshark while recreating the problem. See if packets are actually being sent to the correct addresses and if there are any replies. |
| B. | Search the Internet. See if others have had the same problem, and if so, how they solved it. |