Logon Process has failed to create the security dialog

Hi, Last week my computer wouldn't run more than 1 application at a time.  I would get a frozen screen (mouse would move but was totally non-responsive), then a blue screen then a "logon process has failed to create the security dialog" error.  I click OK and return to a non-responsive computer.  After reading many of the posts from 2008 regarding my "logon process" error, I disabled my Windows Defender.  That seemed to do the trick until I tried to open PowerPoint.  Every time I try to open PPT, it won't load -I get  a blue screen for the PowerPoint program and nothing loads, everything freezes, etc.  I uninstalled and reinstalled my Office 2007 files and still nothing.  I even followed some directions regarding a "Scan for and attempt recovery of bad sectors" and that didn't work.I'm not at all computer literate so any responses will need to be pretty Step-by-Step...sorry.Thank you SO much.  I barely have any hair left as I've been pulling it all out?!?!1?Jen I accidentally posted this in the wrong topic...sorry.


Post Originated from http://www.VistaForums.com Vista Support Forums