Anti-virus manufacturer Dr Solomons claims that the latest version of Windows 95 contains a design glitch that could make it hard to fix an infected hard drive.
Dr Solomons' Mike Hill said the Windows95b version, which is known in this country as OSR2, cannot produce a complete boot-up system disk for use in emergencies. "It produces a cut-down disk, which instead of running a complete operating system, only bypasses the systems files and goes straight to the partition sector of the hard drive," Hill said.
As the partition sector of the hard drive is where many types of viruses are stored, the conventional technique - switching off a virus-infected computer and rebooting with a clean floppy system disk to remove the virus - will not work.
"All that will happen is that you will probably infect the floppy you have just installed or the virus will be able to go memory resident and infect the rest of your files," Hill said.
The OSR2 versions of Windows 95 are being installed as standard in machines in the US and are available to Microsoft users who have installed the service pack number two. These versions of Windows 95 are expected to be shipped to the UK and Europe this month.
Microsoft was "surprised" that the new version of the program would be susceptible to virus repair problems. Windows95 software designers are investigating the issue, a spokesperson said, to see whether Dr Solomons is correct. The company expects to make a statement later next week.
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