The most popular among Microsoft certifications is MCSE, Microsoft Certified Systems Engineer. MCSE consists of Core subjects and Optional subjects. One need to pass 5 core exams and 2 optional exams to obtain MCSE certification. The core exams . Microsoft expects all Windows 2000 MCSE candidates to have at least one year of hands-on experience in implementing and administering a network operating system to pass the exams, and the core exams demand that the candidate have troubleshooting skills acquired through hands-on experience and working knowledge.
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You can obtain the practice tests for MCSE certification here.