Many the only ones I know of are just a small handfull of how many there could possibly be (torojan horse, some kind of weird name like Bot ___, and a few others) the closest number is 300
However many were needed. If a company ordered 200 computers from Microsoft, Microsoft would make 200 computers.
There are no active viruses that affect Mac OS X.
If you go to the Microsoft website, they have several different "how to" guides for many different types or errors and problems, including a check for Microsoft viruses.
no it causes many viruses to computers
YOU don't infect other computers with viruses.
That's easy - NONE. Microsoft sells software not hardware.
No, as Microsoft doesn't make computers.
all computers have Microsoft on them because that's the brand name that designed and made the computers
Microsoft don't sell computers. Microsoft is a software compamy
You can get them in web pages, for example cookie viruses.
None - Microsoft doesn't make computers. They make computer software.
Anti virus is made by many companies to protect computers from viruses.