In addition to the systematic, layered approach to troubleshooting, there are also, less-structured troubleshooting approaches.

One troubleshooting approach is based on an educated guess by the network administrator, based on the symptoms of the problem. This method is more successfully implemented by seasoned network administrators, because seasoned network administrators rely on their extensive knowledge and experience to decisively isolate and solve network issues. With a less-experienced network administrator, this troubleshooting method may be more like random troubleshooting.

Another approach involves comparing a working and non-working situation, and spotting significant differences, including:

Using this method may lead to a working solution, but without clearly revealing the cause of the problem. This method can be helpful when the network administrator is lacking an area of expertise, or when the problem needs to be resolved quickly. After the fix has been implemented, the network administrator can do further research on the actual cause of the problem.

Substitution is another quick troubleshooting methodology. It involves swapping the problematic device with a known, working one. If the problem is fixed, that the network administrator knows the problem is with the removed device. If the problem remains, then the cause may be elsewhere. In specific situations, this can be an ideal method for quick problem resolution, such as when a critical single point of failure, like a border router, goes down. It may be more beneficial to simply replace the device and restore service, rather than troubleshoot the issue.