FLINT HILLS TECHNICAL COLLEGE
Network Troubleshooting Flowchart

START
Windows Workstation Unable to Access a Network Service
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.
Do other workstations on the LAN have the same problem?
Yes  or  No
        ↓
Restart the affected workstation. Problem solved?
Yes  or  No
        ↓
Is the Link-Light on the NIC lit?
Yes  or  No
↓        
Execute: ipconfig /all
What type of IP address?
No IP address  or  Valid Static or DHCP  or  DHCP starting with 169.254 (APIPA)
↓                        
ping the destination by name. Successful?
Yes  or  No
               ↓
ping the destination by IP address. Successful?
Yes  or  No
               ↓
ping the default gateway’s IP address. Successful?
Yes  or  No
↓        
Possible Solutions
A. Incorrect subnet mask or default gateway. Compare with the settings on another workstation that is working on the LAN.
B.  Bad entry in local routing table. View it using the route print command, and compare it with the routing table on another workstation that is working on the LAN.
C. Misconfigured firewall. Disable Windows firewall. Check with admin of network firewall to see if workstation is being blocked.
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.
Problem Solved?
Document Your Solution
FINISHED

Click here for a graphical version of this flowchart.