Memory errors in Windows 2000

I am getting memory errors on my Compaq Armada M700 running Windows 2000. I do not recall these errors when I was running NT 4. The errors are as shown below and do do apply to Word 2000 only.
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Winword.exe – Application Error

The instruction at “0x10010523” referenced memory at “0x00000000”. The memory could not be “read”

Click on OK to terminate the program
Click on CANCEL to debug the program
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Any idea what is causing this? Is it hardware, OS or application problem?