Hello, is use the latest avast home. When i start my computer, the following message appears: Error 1 start OS. This may be due to a virus.
1.shutdown
2.boot from floppy
3.run Ontrack manager
4.select upgrade from advanced options
Is there a tool to ignore my Maxtor Dynamic Drive Overlay?
Your antivirus mark this as a virus.
Please, give us more elements (your pc specs and software specs) and the list of the programs running on your pc. In case of virus infection, try to remove the virus and boot the computer to a DOS prompt from a virus-free floppy disk
Welcome on this Forum. 
Windows 98 SE
Maxtor Diamondmax 8+
Pentium 3 500 MHz
latest avast home (4.6) dutch
multiple users
Hp vectra vei8 (=motherboard)
Hewlett Packard (=bios)
mmm… the message “Error 1 start OS” normally (if I’m not wrong) is referred to a broken master boot record. I don’t understand why you are so sure about the DDO is related to it. Your partitions are ok? Your BIOS see the exact dimension of your HD? I know how sometimes there are problems in deleting viruses in presence of a DDO but
I’m not sure this is the case.