Answer: We don't know. We suspect. We think we know. Sometimes we are right and sometimes we are wrong. Sometimes we are right for the wrong reason and sometimes we are wrong for the right reason.
If you have the "formb" virus we will be right, there is only one answer. Others mangle things depending on what is installed and some mangle things depending on what is run later. So we waffle out of firm answers.
THE ULTIMATE ANSWER REMAINS, as it has always been, the use of a competent anti-malware package with current signatures.
Some virii can be removed by using a virus checker loaded on a clean boot (power down for 10 seconds prior to booting from a known clean boot floppy) from the install floppy using the virus signatures also provide on floppy.
Some can be removed by the loaded virus checker.
Some can be removed by using a fix tool supplied by anti-virus companies.
Some can be removed by running a virus checker with updated signatures.
Some can be removed by use of an online scanner.
You might thy the following sites: http://www.grisoft.com
and download a free (to individuals) package
We haven't used them, so we can't give evaluations of the services.
Some virii can't be corrected immediately, or ever, or the damage is so great that the system never runs correctly after the infection. In those cases, the only solution is to reload the operating system from the very beginning.
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