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faq:dep_data_execution_prevention_disabling

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faq:dep_data_execution_prevention_disabling [2018/06/14 14:52 (6 years ago)] swindfaq:dep_data_execution_prevention_disabling [2018/06/14 15:02 (6 years ago)] (current) – [What is DEP??] swind
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 ====== Disabling DEP ====== ====== Disabling DEP ======
  
-Data Execution Prevention has been known to interfer with System Five and Pervasive if set to "**Turn on DEP for all programs and services except those I select**"+Data Execution Prevention has been known to interfere with System Five and Pervasive if set to "**Turn on DEP for all programs and services except those I select**" 
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 ===== To Disable DEP on a Windows Server / Windows 10 Workstation perform the following: ===== ===== To Disable DEP on a Windows Server / Windows 10 Workstation perform the following: =====
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 +{{ :faq:dep-10.jpg?800 |}}
  
 Open Control Panel Open Control Panel
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 ====== What is DEP?? ====== ====== What is DEP?? ======
 *More information on DEP and what it is: *More information on DEP and what it is:
-(Taken from Mictosoft's WEB Site)+(Taken from Microsoft's WEB Site)
  
 Data Execution Prevention Data Execution Prevention
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 When the system runs with PAE disabled, drivers for 32-bit devices never require their map registers to be backed by real memory. This means that double-buffering is not necessary, since all devices and drivers are contained within the 32-bit address space. Based on testing of drivers for 32-bit devices on 64-bit processor–based computers, it is expected that most client-tested, DMA-capable drivers expect unlimited map registers.  When the system runs with PAE disabled, drivers for 32-bit devices never require their map registers to be backed by real memory. This means that double-buffering is not necessary, since all devices and drivers are contained within the 32-bit address space. Based on testing of drivers for 32-bit devices on 64-bit processor–based computers, it is expected that most client-tested, DMA-capable drivers expect unlimited map registers. 
  
-To constrain compatibility issues, Windows XP Service Pack 2 includes hardware abstraction layer (HAL) changes that mimic the 32-bit HAL DMA behavior. The altered HAL grants unlimited map registers when the system is running in PAE mode. In addition, the kernel memory manager ignores any physical address above 4 GB. Any system RAM beyond the 4 GB barrier would be made unaddressable by Windows and be unusable in the system. By limiting the address space to 4 GB, devices with 32-bit DMA bus master capability will not see a transaction with an address above the 4 GB barrier. Because these changes remove the need to double-buffer the transactions, they avoid a class of bugs in some drivers related to proper implementation of double buffering support.+To constrain compatibility issues, Windows XP Service Pack 2 includes hardware abstraction layer (HAL) changes that mimic the 32-bit HAL DMA behavior. The altered HAL grants unlimited map registers when the system is running in PAE mode. In addition, the kernel memory manager ignores any physical address above 4 GB. Any system RAM beyond the 4 GB barrier would be made un-addressable by Windows and be unusable in the system. By limiting the address space to 4 GB, devices with 32-bit DMA bus master capability will not see a transaction with an address above the 4 GB barrier. Because these changes remove the need to double-buffer the transactions, they avoid a class of bugs in some drivers related to proper implementation of double buffering support.
  
 As a result of these changes to the HAL and memory manager, the impact to device driver compatibility is expected to be minimal on systems running Windows XP Service Pack 2 with data execution prevention enabled. As a result of these changes to the HAL and memory manager, the impact to device driver compatibility is expected to be minimal on systems running Windows XP Service Pack 2 with data execution prevention enabled.
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 The DisableNX compatibility fix can be applied to an application by using the Application Compatibility Toolkit. For more information about Windows application compatibility, see “Windows Application Compatibility” on the Microsoft Web site at http://go.microsoft.com/fwlink/?LinkId=23302. The DisableNX compatibility fix can be applied to an application by using the Application Compatibility Toolkit. For more information about Windows application compatibility, see “Windows Application Compatibility” on the Microsoft Web site at http://go.microsoft.com/fwlink/?LinkId=23302.
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 +Updated by Steve Wind June 14 2018
  
  
faq/dep_data_execution_prevention_disabling.1529013136.txt.gz · Last modified: 2018/06/14 14:52 (6 years ago) by swind