Don't take this the wrong way, but if your resume reads like your post, then I would start by re-writing your resume and getting someone to review it with you. There were a lot of typos in the posting. I had the same problem for over a year due to an auto-correct I missed. Changed Virtualization to Visualization. Once that was pointed out to me, and I fixed it (And it was the only fix) the calls started pouring in.
What format are you using for your resume? Since it's been a few years, I would focus on the Functional resume over the Chronological one. If you have any IT / InfoSec related volunteer experience find a way to work that in to the resume too.
Lastly, what's your twitter handle? It really is who you know not what you know. Even though I changed jobs this year, I submitted my resume to HR and didn't get past the filter, it took people I knew there that got me to apply to get me the interviews. In one case, the job posting was written using my resume and HR said I wasn't qualified. (It was a position I had been doing as a contractor, and my managers were trying to hire me full time).
This is true for other people I know too. You need to be a known person in the community, once you are you'll find people that will help get you past HR for the interviews.