CIH VIRUS FREE Data Recovery! |
were damaged by the CIH Virus.
The CIH virus attempts to ERASE the writable FLASH BIOS of infected PC's, and also overwrites the first 2,048 sectors (1,048,576 bytes) of all of the system's available non-removable writable disk drives! While this behavior places the CIH virus among the nastiest of all viruses, the damage is more recoverable than at first appears:
Flash BIOS Recovery: (Please note that Gibson Research Corporation has no special expertise in Flash BIOS recovery so we can not help you there. If your system's Flash BIOS was erased you must either move your hard drive to a system with a working motherboard or repair your BIOS before proceeding to consider the recovery of your system's hard drive.)
Hard Drive Recovery: (Note that our standard SpinRite product was never designed to recover from deliberate and malicious damage done to drives by virus activity. SPINRITE DOES NOT RECOVER FROM THE DAMAGE DONE BY THE CIH VIRUS. Steve has researched the problem and now offers a completely FREE solution for everyone.) How is it possible to recover the loss of the first 1 million bytes of a hard disk drive? The "front" of a DOS/Windows hard disk drive contains the following crucial information:
Recovering from the Loss of the First Megabyte: The restoration of the drive's Partition Table (which is the first thing Steve's new FREEWARE program does) will immediately restore the drive's partitions to existence. Although the CIH virus does extensive damage to the first partition, subsequent partitions are left completely intact!
Recovering the Drive's First Partition: With the advent of 32-bit File Allocation Tables (FAT32) the FAT tables became quite large ... and this is the second part of the secret behind completely recovering from the loss of the first megabyte of the hard drive. For example, a one gigabyte drive (or partition) formatted with a 32-bit FAT will consist of approximately 262,144 clusters of 4,096 (4k) bytes each. Since each FAT table entry requires 32-bits, or four bytes, a single copy of the FAT for a one gigabyte drive will require exactly one megabyte of sectors! So, since just the first copy of a 32-bit FAT for a one gigabyte drive requires one megabyte of storage, and since the CIH virus only erases the first one megabyte of the drive, the large size of this first FAT table pushes the entire second copy of the FAT and the root directory fully out of harm's way!
This means that by first reconstructing the Partition Table and the Boot Sectors and then copying the second (preserved) copy of the FAT down into the space where the first copy belongs ... the first partition of the drive (if it's at least one gigabyte and FAT32 format) can be completely reconstructed and recovered!
As we said above, for drives with more than one partition of any format, the partitions beyond the first can always be completely recovered by the reconstruction of the drive's partition table. (Which is one of the things that Steve's new FREEWARE program does.)
So, even if your C: partition was FAT16 format (and thus not completely recoverable from a CIH attack) your D:, E:, and other partitions can be completely recovered automatically!
FIX-CIH to completely recover from CIH attack! Since this pesky CIH virus has just damaged hundreds of thousands of hard disk drives, Steve Gibson created a new FREEWARE program to recover from this problem . . . even AFTER the virus has wiped out a drive! This program quickly recovers FAT32 formatted drives from the damage done by the CIH virus. (Note: Unfortunately, it will not be able to help non-FAT32 formatted drives.) So, if your system has just been zapped by the CIH Virus, if you have your flash bios working again (or if it wasn't zapped) but after booting DOS from the A: (diskette) drive your hard drive is gone, unrecognized, or missing ... the program Steve has written will repair your drive and recover ALL of your data! The FIX-CIH Research and Development Diary page has information about the development of the program. The FIX-CIH Download and Version History page contains a link to download the FIX-CIH program and information about its various versions. |
FIX-CIH Research and Development Diary |
FIX-CIH Download and Version History |
FIX-CIH Recovery Stories |
CIH Virus Info Home Page | Steve's Page |
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Last Edit: May 25, 2005 at 14:10 (7,136.08 days ago) | Viewed 27 times per day |