If it's not too much of a risk for you, it may be worth posting some system information like your operating system, general system specs, and when this started happening. It is very possible that this isn't to do with the StallServer itself, especially since you said at one point it was working for 100 hours before crashing. I know it's old, but see https://social.technet.microsoft.com/Forums/windowsserver/en-US/8d29f351-6bc4-4ad8-9fcc-02d827e05536/ephemeral-port-exhaustion-event-id-4231?forum=winserver8gen for a previous example of the issue happening because of a Windows update. Perhaps you could post your Windows event logs from around the time it is happening too.