How I do to increase System PTE's on Windows 7 Professional, and how I do to get these to extend over the pagefile?

Here is my problem: Currently, Im configuring computers at a internet café. To prevent customers from installing viruses and such things, and make a jerk out of the computers, Im running "ewf" (Enhanced write filter) in RAM-REG mode. Thus, any Changes that are made to the computers are wiped at reboot, putting the system in a "fresh" state each boot.

The computers do have a protected drive (700GB) and one unprotected (64GB). The computers do have 16 GB of physical RAM.

On the unprotected drive, I have placed a pagefile of 50 GB. Thus there should be 66 GB of memory for the system to store disk overlays in.

But regardless of if page file are enabled or disabled, the system stalls when changing more than 6 GB of data is changed on the harddrive. I googled on the problem, and found this page: http://blogs.msdn.com/b/windows-embedded/archive/2009/11/17/ewf-overlay-limits-on-windows-embedded-standard-2009-and-2011.aspx

Apparently the System PTE's are exhausted Before the system get any chance to swap the pages to page file. I googled more and apparently System PTE's is managed automatically by windows and are NOT extended over page file.

Is there any "registry hack" that I can do to:

1: Increase System PTE's

2: Have them extend over page file.

I would also appreciate any other solutions that can be used to solve the problem, for example installing third party software that would make the system Think the page file is part of physical ram (instead of virtual ram).

I tried to increase the SystemPages property to max (0xFF...FF) but it didnt have any effect.

  • 32-bit Windows or 64-bit? If they are 32-bit, you get far more PTEs with 64-bit. blogs.technet.com/b/clint_huffman/archive/2008/04/07/… "64-bit Windows has much higher amount of memory available System PTE’s. Specifically 64-bit has a maximum memory size of 128GBs for PTE’s while 32-bit Windows has a 660MB maximum for PTE’s. For more information, see support.microsoft.com/kb/294418. " May 7, 2015 at 14:33
  • I used to work for a software co. and running out of PTEs was a fairly common problem on 32-bit servers that had more than two or three third-party filter drivers. Although ewf isn't third-party, it's one that does a lot of work similar (or even more intensive) than anti-virus or file replication and needs a lot of resources. May 7, 2015 at 14:58
  • Still thinking about this--if there are any filesystem-related applications that have a filter driver installed, uninstalling them would help if they aren't necessary (but help enough, I don't know). It isn't too likely that you have anything like this that could be uninstalled. If you have antivirus installed, you might try something different as it could be contributing to the problem. If you could test without antivirus--if the problem still occurs then you know that using a different antivirus is not a solution. May 7, 2015 at 15:29
  • I want to shoot Microsoft. On the article which explains what System PTEs, it doesn't explain, what PTE stands for.
    – Ramhound
    May 7, 2015 at 15:43
  • Page Table Entries May 7, 2015 at 15:46

1 Answer 1


The only ways to get more available PTEs are:

  • Use a 64-bit (128 GB available for PTEs) installation of Windows instead of a 32-bit (660 MB available for PTEs). See https://support.microsoft.com/en-us/kb/294418

  • Uninstall any unneeded software that has a filesystem filter driver running. To see what filesystem filter drivers are running, start MSINFO32.EXE and go to the Software Environment/System Drivers node. Sort on the Type column and review those that are File System Driver

  • Set the SystemPages registry setting to 0xFFFFFFFF. https://technet.microsoft.com/en-us/library/cc976159.aspx Please note that this may have significant unintended consequences, so please test thoroughly.

  • Contact the vendors of the application that is failing or causing excessive PTE usage. They may have a defect, or an undocumented configuration item to address the issue.

  • The system is 64 bit. The application that causes excessive PTE usage is EWF (Enhanced filter driver) that is of course, storing all Changes made to the file system in RAM. So I want to forcefully increate PTE to span over the page file. I tought it was clear from the question that the system was 64 bit because of the 16 GB ram. May 7, 2015 at 23:10
  • You're quite welcome for the time I spent trying to shed some light on the situation. I listed all of the ways I know to deal with it--I apologize for not knowing how to accomplish something that is undocumented, and probably not even possible. May 7, 2015 at 23:24
  • System PTEs cannot themselves be pageable, hence they can't "extend over the pagefile". Apr 17, 2016 at 22:38

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