How do I move forward?

I have been doing break/fix desktop support for 2 years. Originally it was supposed to be a get my foot in the door job, but now I feel stuck and I’m growing unhappy. I eventually want to be a network administrator or get into IT security, but I’m really not sure how to get there. I got my MCSE in 2006, but haven’t really used it and don’t remember a lot. Just looking for tips to get where I want to go.

Thank you,
Adam