This is a Microsoft Excel macro virus. Sofa spreads to Excel spreadsheets once it has copied its virus code to the default startup directory. It does this by creating a file called \MSOFFICE\EXCEL\STARTUP\BOOK.XLT
Sofa contains these macros: Auto_Open, Auto_Range, Current_Open, and Auto_Close.
Sofa activates by checking the title bar text of Excel to read
Microsofa Excel
Otherwise, the virus just spreads.
Sofa was found in the wild in USA in December 1996.
See: ExcelMacro/Laroux
Based on the settings of your F-Secure security product, it will either move the file to the quarantine where it cannot spread or cause harm, or remove it.
A False Positive is when a file is incorrectly detected as harmful, usually because its code or behavior resembles known harmful programs. A False Positive will usually be fixed in a subsequent database update without any action needed on your part. If you wish, you may also:
Check for the latest database updates
First check if your F-Secure security program is using the latest updates, then try scanning the file again.
Submit a sample
After checking, if you still believe the file is incorrectly detected, you can submit a sample of it for re-analysis.
Note: If the file was moved to quarantine, you need to collect the file from quarantine before you can submit it.
Exclude a file from further scanning
If you are certain that the file is safe and want to continue using it, you can exclude it from further scanning by the F-Secure security product.
Note: You need administrative rights to change the settings.
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