Privacy, Security & Virus Information

What is a micro virus?

If you're asking yourself what is a macro virus, just think about what macros are and how they are employed in applications such as Microsoft Word and Microsoft Excel.

Macros are commands which handle often repeated tasks in a set and automated sequence. Think about a spreadsheet and how it can be instructed to add, or divide certain columns of figures in a certain way. At the basis of this functionality is a macro command.

Right, and a macro virus emulates a macro command, written in the same way and is embedded in a document, or spreadsheet. It activates when the said document, or spreadsheet activates, and then sets about its set tasks (whatever evil intent pre-determined by the virus originator).

It is estimated that nearly three-quarters of all viruses out there are macro viruses. Although they are picked up by anti-virus software, they are tricky to handle because they infect documents and spreadsheets, and their templates, and not the main computer programmes.

Thus, they can sit undetected for some time and should someone access an old document, they could be reactivated after a period of dormancy.

The most popular way that a macro virus spreads is as an email attachment. It sits hiding inside the document, or spreadsheet, and unless the recipient's computer is fitted with good anti-virus software and is set to scan all incoming (and indeed outgoing emails), as is best practice, the macro virus will activate once the document, or spreadsheet is opened.

So, it's best to ensure that all incoming and outgoing emails are scanned for nasty viruses.

And some programmes are more susceptible than others, with chat rooms highlighting key problem areas. This is often a good way of finding out in which area you should take more care.

But if you suspect that you might have a macro virus, you can have a delve around and see if your suspicions are confirmed. Firstly, you have to launch the programme that's being suspected. Secondly, go to Tools and choose the sub menu Macros. If there are any macros, they will be listed here. If you find some of the following names, then you might have an embedded macro virus: Auto_Open; Check_files; PERSONAL_XLS!auto_open; or PERSONAL_XLS!check_files.

Within a corrupted Microsoft Excel spreadsheet, you might find !check_files, or !auto_open.

Another way is to go into say the Excel directory and see if you can find any files labelled PERSONAL.XLS. as this would denote a macro virus.

But, with virus names constantly changing, even this quick check might not put your mind at rest completely.

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