How to Check for a Boot Sector Virus

By Nina Rotz

Fragmentation leads to a lack of free memory available for computer tasks.
i Brand X Pictures/Brand X Pictures/Getty Images

Computer hard drives consist of sectors, and each sector contains a segment of data. The boot sector is the first sector of every hard drive. A boot sector virus, which comes from an infected floppy disk, affects the first sector of a hard drive.

The boot sector of the infected hard drive loads first, sending the virus into every partition and piece of data. The virus infects the computer's memory or RAM. Computer processors are incapable of reading or writing data if their RAM is corrupted. The virus will subtract 2,048 bytes of total memory available when a disk check is performed. Symptoms of a boot sector virus are missing files on the hard drive, corrupt system files and failure of the computer to start up.

How to Find Computer Memory Size

Step 1

Click "Start" and choose "My Computer."

Step 2

Right-click the "Local Disk (C:)" icon and select "Properties." A new window will open.

Step 3

Scroll down to see the system information.

Step 4

Locate the "Memory (RAM)" section. Write down the amount of memory listed on a piece of paper. The memory amount will be shown in GB, or gigabytes.

Step 5

Convert Gigabytes to bytes. 1 Gigabyte is 1,073,741,824 bytes. Write down the converted memory amount on a piece of paper.

How to Run Disk Check

Step 1

Click "Start" and select "All Programs."

Step 2

Click "Accessories" and choose "Command Prompt." A black screen will appear.

Step 3

Type "chkdsk" in lowercase letters and without quotations. Press the "Enter" key on your keyboard to perform a disk check.

Step 4

Allow several minutes for this process to complete.

Step 5

Look for the line "Total Bytes Memory" once the disk check has ended.

How to Determine Whether There Is a Boot Sector Virus

Step 1

Read the information provided by the disk check.

Step 2

Determine a Boot Sector virus is present if the total bytes of memory is 2,048 bytes less than the amount show on the disk drive properties. Compare the command prompt memory amount and the memory amount written down on paper. For example, 1 Gigabyte of memory is 1,073,741,824 bytes. A present Boot Sector virus will show 1,073,739,776 bytes.

Step 3

Type in "exit" and press the "Enter" key to exit the command prompt.

×