Asus has admitted that Eee Box PCs released in Japan last week were infected with a virus. So far it would seem that the incident only affects systems sold in Japan, but that fact has not yet been confirmed by Asus.

The virus is reported to be the W32/Usbalex worm, which comes as a hidden file on the D: drive; a partition of the 80 GB hard drive. The virus apparently is contained in a file named recycled.exe, which is triggered to run when the D: drive is opened, thanks to the use of an autorun.inf file.

Once executed, the virus attempts to copy itself to the main C: drive partition and any other connected drives, such as USB flash drives or networked mapped drives. According to Symantec, the virus only affects Windows computers, has a low damage level and is easily removed. It is not yet known how the virus found its way onto these computers and whether or not the infection was intentional.

The Asus Eee Box PC is considered to be a nettop, which are essentially inexpensive Internet-centric desktop PCs. The particular model of Eee Box PC that is known to be infected is the Eee Box B202, which uses the Windows XP Home operating system. The system also features an Intel Atom N270 processor, 1 GB of memory, gigabit Ethernet, 80 GB hard drive, 802.11n and DVI-out. Nettops do not offer high-performance, but they are quickly becoming popular due to their low price, small size and power efficiency.