The present invention tests computer systems for defects that are able to cause performance and functional problems. An agent application is first installed on a user's system. The agent application then retrieves problem data from the expert system library pertinent to the user's operating environment. The agent application tests the user's system for each problem description within a downloaded data structure from the expert system library. If a problem is discovered, a script attempts to remediate the problem and/or notifies the user, describing the issue. If an unknown problem arises, a feedback mechanism sends a notification to the expert system library that a problem was discovered. The feedback is then utilized to increase the total knowledge in the expert system library. Then when another user with a similar or the same setup is tested, the agent application will recognize the issue and will take the appropriate remedial actions.