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Category: Malware

Type: -

Aliases: nul, prn, lpt1, clock$


This is not a virus. Actually, the typical support query goes like this:

Question: I found a file called "nul" in my root directory. I can not access or delete it. Later I found it existed in each and every directory! This has to be a virus!

Answer: How did you find it? With which program?

Try locating in a same manner files with names such as "lpt1", "prn", "com1", "clock$" and you will see that they too exist in every directory and can not be accessed or deleted. This is normal and is a feature of DOS.

These are virtual names for system devices: prn for printer, nul for null port, clock$ for CMOS memory etc. Ignore them.


Automatic action

Based on the settings of your F-Secure security product, it will either automatically delete, quarantine or rename the detected program or file, or ask you for a desired action.

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About the product

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