RALEIGH — Another computer virus is scheduled to strike Monday, but this one is a lot worst than the Melissa bug that spread last month.

The virus is set to activate Monday, the anniversary of the Chernobyl meltdown in Russia.

Warnings about the CIH virus are all over the Web. The virus hits each month on the 26th day, but April 26th is the most devastating.

CIH will destroy data on users hard disk, and make the machine inoperable. The best advice is to update the computer's antivirus software, and run it this weekend, and run it again after Monday.

Trend Microoffers its antivirus scan free. The CIH viruscan be spread within e-mail or in pirated software. It hides in the hard drive and can lie dormant for months.

Another security issue came to light this week. E-commerce is growing, but some people buying online are spreading their personal information all over the Internet.

The electronic business problem stems from improper installation of so called "shopping cart" software used by hundreds of online stores. A Cancun travel agency is one of the sites from which personal information was downloaded.

Most mainline e-commerce sites are very secure; however, some Internet experts say the rush to do business online has brought about some shoddy e-commerce installations.

As a rule of thumb, trust sites operated by major businesses when buying online.

It is expected the CIH virus will affect more home computers than those used in businesses. Most business operations routinely run antivirus software; however, many home users do not keep their antivirus programs updated - that practice is always time well spent online.