We specializing in both large corporate sites, small business e-commerce along with smaller personal sites for web design. We are located in Denver Colorado and Mississippi. There are many good antivirus programs on the market. My personal recommendations for antivirus programs are Symantec's Norton Antivirus. In addition to installing the program, you need to ensure it is updated monthly.
Most companies provide free updates to their products.
Update Monthly or Twice Monthly. It has been said over 600 new virus's a day come out. Check your disks for errors. Errors occasionally happen in the file and directory systems. If they are not found and corrected, they can grow and can potentially disable a system.