The best thing is to make a list of softwares those are running in your servers. Then call their vendors and ask them about their services. It will take your one or two hours but you will be safe.Like we are running Microsoft Exchange Spamkiller from Network Associate and they have password setting in the componets objects too. Another way is, you can change the password then restart the system and then try to check the event log. If any application will fail it will log its entry in application log so you will have the list of softwares those are depending on your password. Is any thing else you need ,We will try our best to help you out Wasalam Abdul Basit