I think I have a serious infection that somehow got past Micrsoft Security Essentials, stopped the program, and prevents all attempts to fix it. I'm running Windows 7 64 bit on an HP Pavilion g series.
A few days ago, my computer randomly shut down while I was browsing the internet- opening a lot of tabs at once, but otherwise not doing anything that should cause any problems. It started up again and everything seemed to be working okay, but I soon noticed that MSE was not functioning. When I tried to restart it, I got a message saying "Couldn't start the Security Essentials service. The specified service does not exist as an installed service." with an error code of 0x80070424. I tried various suggestions from help websites that related to the code, including running MalwareBytes. Both quick and full scans found issues, but upon restart, this problem remained unchanged.
Finally I decided to go ahead and uninstall and reinstall MSE. Everything went fine until the initial scan started. Very early on, I got a message saying my computer would have to restart to remove infections. Then I got a message from Windows saying that Windows had encountered a critical problem and would restart in one minute. On every restart, MSE would start finding issues and trying to restart the moment the computer started up and eventually that Windows message would come up, shutting me down again.
Finally I used f8 and tried to run a system restore. I got an error message on all available restore points, but when I let the computer shut down and restart, it restored itself to a point before I tried to fix MSE. MSE was still non-functioning, but my computer started up and ran all programs with little issue. The same thing happened when I tried to run an automatic Microsoft fix-it for MSE/Windows Update. Halfway through running, I got the critical problem warning and ran the same system restore process to be able to use my computer. But now I'm using it without protection.
The actual problems caused by this infection(?) aren't actually all that severe. Random pop-ups to spammy websites and issues with Google search where I can search just fine, but clicking on results will usually take me to another spammy site. But, of course, I can't use MSE and doubt I can run Windows updates, either.
I'm certainly hoping I don't have to completely restore the machine, although my important files and pictures are backed up and I can back up the rest fairly easily. I'm especially frustrated because this is a new-ish machine (Between 6 months and a year old) and I've been very careful not to do anything that could potentially be considered unsafe. Any help would be very much appreciated, as is just reading through my long explanation!
*Moderator Edit: Moved topic from Windows 7 to the more appropriate forum. ~ Queen-Evie*
Edited by Queen-Evie, 29 July 2012 - 06:50 AM.