Z-90 activates in July and December if an infected file is executed and the time is exactly 09:03. At this time the virus encrypts the DOS boot sector of drive C:, making the PC unbootable (encryption is done by XORing with 16-bit hex value 0903). After this it displays this message:
VIRUS Z-90. JUNIO 95. M EXICOSE MURIO TU DISCO DUROTU LO PUEDES RE VIVIRHAS BAILADO ALGUNA VEZ CON TU NOVIA A LE TENUE LUZ DE LA
Z-90 was found in the wild in Brazil in April 1996.
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.
Ask questions in our Community .
Check the user guide for instructions.
Submit a Sample
Submit a file or URL for analysis.