There are several things that could cause this problem. You must have administrative access to complete these steps.
1. The memory is incorrectly seated or damaged. check that it is seated correctly. If this doesn't help, run the memory diagnostic tool. In Vista it is C:WindowsSystem32MdRes.exe. I don't know about 2003 server ed.
2. Memory capacity has been restricted in the registry. This has actually happened to me before. I don't know much about 2003 server ed., so I'll assume that you have msconfig.
If this doesn't help, or you can't find msconfig, please private message me through my profile if you need more assistance.
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