Lately, we've had problems twice with the TimeTrax recorder at work. It can still be pinged but the software (ver. 4.3.1) cannot reach it. Something about communication ports being not available.
I believe during the first time, I tried to reset the recorder, changing its IP, and perhaps restarting the server, in order to solve the solution. As with the second time (yesterday), I tried to solve it avoiding to restart the server, did not work. Since I didn't want to restart the server, it took me a long time to resolve it. I even called the customer support but they said it they don't support their software on the server. And if I were to upgrade or recover a lost copy, we need to pay $175 for the new version, which is supposed to have more net configuration feature.
Solution:
I noticed with netstat -a, a lot of UDP ports were listed. So, I thought it was the cause. A search online led me to find a way to close those ports: net stop dns, and, net start dns. Simply stopping the dns works already.
Other than that, I should look into what these latter commands really do.