Complete memory dumps are not available on the following computers if they have 2 or more gigabytes (GB) of RAM:

•	Microsoft Windows Server 2003-based computers
•	Microsoft Windows XP-based computers
•	Microsoft Windows 2000-based computers
•	Windows Vista-based computers

The only options available under Write Debugging Information in the Startup and Recovery dialog box in System Properties are Small Memory Dump (64 KB) and Kernel Memory Dump. The Complete Memory Dump option is not available.

If you set the CrashDumpEnabled DWORD value to 1 in the registry to enable a complete memory dump on a computer that is running Windows XP, or Windows 2000, the memory dump may become corrupted when your computer stops unexpectedly.

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Important We recommend that you consider the following information before you enable a complete memory dump on a computer that has more than 2 GB of RAM:

•	It can take a substantial amount of time to create a complete memory dump on a computer with more than 2 GB of RAM. This can reduce overall system uptime.
•	A complete memory dump on a computer with more than 2 GB of RAM requires a very large system partition because of the paging file size requirements. If you select this option, you must have a paging file on the boot volume that is sufficiently large to hold all the physical RAM plus 1 MB. The extra megabyte is required for a complete memory dump file because Windows writes a header in addition to dumping the memory contents. The header contains a crash dump signature and specifies the values of some kernel variables. The header information does not require a full megabyte of space, but Windows sizes your paging file in increments of megabytes.
•	A complete memory dump file is rarely required. In most cases, a kernel memory dump is sufficient for analysis. Please consult your escalation channel before enabling the complete memory dump in a production environment.
•	If your computer has more than 4 GB of RAM, you must configure the Boot.ini file to start the computer with the Physical Address Extension (/PAE) switch. For more information, click the following article number to view the article in the Microsoft Knowledge Base: 291988 (http://support.microsoft.com/kb/291988/) A description of the 4 GB RAM Tuning feature and the Physical Address Extension parameter

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Windows Server 2003, Windows XP 64-bit Edition Version 2003, Windows XP Professional x64 Edition, Windows Vista

To specify that you want to use a complete memory dump file by modifying the registry, set the CrashDumpEnabled DWORD value to 1. For example, type the following information at a command prompt, and then press ENTER:To specify that you want to use the D:\Dump\Mem.dmp file as your memory dump file by modifying the registry, set the DumpFile expandable string value to D:\Dump\Mem.dmp. For example, type the following information at a command prompt, and then press ENTER:To specify that you do not want to overwrite any previous kernel or complete memory dump files by modifying the registry, set the Overwrite DWORD value to 0. For example, type the following information at a command prompt, and then press ENTER:Note The Write Debugging Information section of the Startup and Recovery dialog box in System Properties continues to list only Small Memory Dump (64 KB) and Kernel Memory Dump after you enable a complete memory dump by using these methods. The Complete Memory Dump option remains unavailable, and you must use the Windows registry to configure complete memory dump options.

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All other versions of Windows XP (including Windows XP 64-bit Edition Version 2002)

You can use either of the following methods to work around this problem:

•	Put the MaxMem=2000 parameter in the Boot.ini file to limit the amount of memory that Windows 2000 can access.
•	Instruct your Windows XP-based computer to create a Small Memory Dump option or Kernel Memory Dump option.

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To work around this problem, use one of the following methods:

•	Put the MaxMem=2000 parameter in the Boot.ini file to limit the amount of memory that Windows 2000 can access.
•	Instruct the Windows XP-based computer, the Windows Server 2003-based computer, or the Windows Vista-based computer to create a Small Memory Dump option or a Kernel Memory Dump option.

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Microsoft has confirmed that this is a problem in the Microsoft products that are listed in the "Applies to" section.

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The following section of the Windows 2000 Datacenter Server Help file incorrectly states that a 4 GB memory dump can be created: For more information about memory dump files, click the following article numbers to view the articles in the Microsoft Knowledge Base:

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Technical support for Windows x64 editions

Your hardware manufacturer provides technical support and assistance for Microsoft Windows x64 editions. Your hardware manufacturer provides support because a Windows x64 edition was included with your hardware. Your hardware manufacturer might have customized the Windows x64 edition installation with unique components. Unique components might include specific device drivers or might include optional settings to maximize the performance of the hardware. Microsoft will provide reasonable-effort assistance if you need technical help with your Windows x64 edition. However, you might have to contact your manufacturer directly. Your manufacturer is best qualified to support the software that your manufacturer installed on the hardware.

For product information about Microsoft Windows XP Professional x64 Edition, visit the following Microsoft Web site: For product information about Microsoft Windows Server 2003 x64 editions, visit the following Microsoft Web site:

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