Due to a botched update, some McAfee Anti-virus users have been informed that Microsoft Excel, a very popular spreadsheet program, is in-fact a virus.
For a while on Friday 10th March, Excel was marked as being the W95/CTX virus. The "false-positive", as the problem is technically known, was due to an error in the definitions file McAfee sent to software users. Definitions files tell Anti-virus software what to look for, and often contains updates to respond to new virus threats.
McAfee Anti-virus dutifully quarantined and moved the files (including core executables such as excel.exe), rendering the Office software fairly useless. After receiving a number of reports from customers, McAfee recognised the problem and rolled out an updated definitions file just a few hours later.
McAfee is not alone in making false-positive gaffes. Last year, Microsoft"s AntiSpyware software flagged Norton Anti-virus as being malicious software.