I haven't tried rebooting in safe-mode or otherwise because I won't be able to reopen any browser (currently the only app running is Firefox, it was open in background all along) I can open My Computer and view files but that's about it, Task Manager, System Restore, Registry Editor, are not working. same error message for each. Really in a tight spot here, not really sure what I should or can do. Thanks for reading/helping if you can.
I downloaded Avast free from CNET to and external HD in order to scan an infected computer without internet. At the end of the download (download successful screen) the usb was disconnected and an error message about windows being unable to compete the file writing (it went away before I had a chance to read all of it) Now any application I try to run says that it is unable to start due to the folder I downloaded Avast to cannot be found. This includes windows system apps like system restore, command prompt, even the clock. I now have one computer down with a virus and the other (that I'm using now) unable to run anything whatsoever. Any help would be immensely appreciated. Thanks in advance.