My server is on Win NT SP4. The TCP/IP listner on my server stops working because of that my users are not able to connect the server. I need to restart the server to enable users login. what can be done to resolve this problem. also if I can upgrade my SP. I couldn't find SP5 to upgrade.
The last update for NT4 is SP6a. You can also find a Security Rollup Pack SRP for NTSP6a which includes all patches post SP6a until the product went end of support. I'm not sure if MS still have the files avalible but good luck.
I think you'll be lucky to find any service packs for NT online. The best bet is to try and find a CD at a computer fair. But, of course, the real answer is that it's long past time that any NT installations were upgraded to something that is still supported. Support for NT ended over 5 years ago, so the situation is only going to get worse.