When using the external build of the Windows Debugging Tools (Windbg) version 6.12.0002.633 and using the external symbol server, you may see an excessive amount of Non-Paged Pool memory usage which exceeds the maximum limits.
The issue is caused by a known problem in the public debug extension kdexts.dll.
Microsoft is aware of this problem and it is under investigation. It is scheduled to be corrected in the next release of Windbg. At this time no release date or correcting version number is available. Since Windbg is incorporated with the Software Development Kit (SDK), the next update may occur with the next major release of the Windows.
To work around the problem you can either download and use one of the previous versions of Windbg or wait for the next released version.
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