After finishing the four core exams for NT 4.0 in 1998, I can't seem to find out when my MCP status will expire. I haven't decided whether to upgrade to 2000 yet because having MCP hasn't really helped me get work. I am also A+ certified and have started Network+ certification.
Your MCP status stays current until 12/31/2001 unless you've also taken an exam that didn't expire already. If that's the case, you have one year from its expiration date before your MCP goes poof! OTOH, if you took 70-073 Workstation, 70-067 Server, and 70-068 Server in the Enterprise, be sure to ask MS to give you a voucher for exam 70-240 because you're eligible to kill off four required exams for your upgrade by taking and passing that single (four-hour 200 question) free exam. That might almost be a good enough deal to justify upgrading your MCSE to 2000 status!
This was first published in March 2001