Just purchased a refurbished laptop for my daughter for Christmas, and had a series of "emergency" notices much the same as the original poster.
Upon further investigation it appears it's a name changing virus that imitates a security program and posts continual fake warnings, won't let you use internet browsers, or run .exe files, and then tries to corner you into entering financial information so it can "fix" your problems. The version of the virus that seems to be affecting my daughter's computer is "XP Security 2012" (seems to be recently referred to on a number of sites like http://www.wiki-security.com/wiki/Parasite/XPSecurity2012, http://www.bleepingcomputer.com/forums/topic434521.html, etc.) I am hesitant to try applying fixes mentioned on varying sites for fear of making anything worse, but I really do also need help in addressing this is
Tried running Norton, and it picked up something, but when clicked to apply the fix, it just shuts down Norton. Also tried running Norton Power Eraser, but it will not allow .exe files to run and it just stops the process.
[edit: Clarified subject.]