The invention partitions the HDD into three areas, namely, no access, write-only, and the conventional read/write. Sensitive data (antivirus programs, back up data, etc.) is written into write-only areas, which thereafter become designated “no access” by appropriately changing their designation a data structure known as “logical block address” or “LBA”. Only users having approved passwords can change the status of a “no access” block back to “write-only” or “read/write”.