Execution Failure Issues

Applies To: Windows 7, Windows Vista

There are several known execution failure issues addressed by the Compatibility Administrator, by using compatibility fixes and compatibility modes.

Fix Name Symptom Fix Description

DisableBoostThread

You regularly receive an access violation error message during application execution.

Disables the automatic boost that threads get when they are unblocked. The Microsoft Windows®°95 operating system and the Microsoft Windows®°98 operating system do this only on message objects, not on synchronization objects.

To change the main thread priority you must use a command prompt with one of the following options:

+HigherMainThread
+LowerMainThread
+BoostMainThread

Where <+HigherMainThread> raises the priority level of the main thread, <+LowerMainThread> lowers the priority of the main thread, and <+BoostMainThread> saves the automatic boost for the main thread.

HeapIgnoreMoveable

The application shuts down unexpectedly during execution.

If the original call to GlobalAlloc fails, this fix calls GlobalAlloc again with the GMEM_MOVEABLE flag removed. The Heap Manager in Windows NT version 4.0 and later operating systems has a 64 KB limit on the number of movable blocks it can allocate.

Important
The EmulateHeap fix supersedes the HeapIgnoreMoveable fix.

HeapLookasideFree

The application shuts down unexpectedly during execution.

Addresses potential problems with freeing heap memory by delaying the freeing of the memory. Also checks to ensure that all heap memory free calls are made on the correct heap.

HeapPadAllocation

The application shuts down unexpectedly during execution.

Addresses potential problems with memory allocation, by allocating additional memory for every call to the HeapAlloc function. By default, there are 256 bytes of extra memory allocated, but you can modify this from a command prompt.

HeapValidateFrees

The application shuts down unexpectedly during execution.

Validates the calls to the HeapFree function to ensure that the specified pointer is in the heap from which it was allocated.

LUARedirectFS

The application shuts down unexpectedly while accessing configuration or user settings.

Redirects files to the SystemDrive\Documents and Settings\username\LocalAppData\Redirected\drive\filepath directory if the user does not have write permission.

DisableScreenSaver

The application shuts down unexpectedly, typically at the same interval at which the screen saver is set to activate.

Disables the screen saver when the application starts, and restores it when the application closes. This compatibility fix is useful for applications using the Microsoft® DirectX® API, which does not work well with an active screen saver.

EmulateHeap

You receive an access violation error message after the application becomes unresponsive.

Emulates the functionality of the Windows 95 and Windows 98 Heap Manager. This compatibility fix is the full implementation of the Windows 95 and Windows 98 Heap Manager, ported to the Windows® XP Professional operating system.

HeapForceGrowable

You receive an access violation error message when the application switches contexts.

Sets the dwMaximumSize parameter to zero, which forces the heap to grow when the HeapCreate function is called.

IgnoreVBOverflow

You receive an error message stating "Runtime error 6" when you install Add-ons to an application.

Intercepts type-checking code and ignores the type check function. Some Microsoft® Visual Basic® applications attempt to store 32-bit handles in a 16-bit variable, which works in Windows 95 and Windows 98, because most handles use only the lower 16 bits of that handle. However, in Windows NT and later operating systems, the handles often use the upper 16 bits of the handle.

IgnoreVBOverflow

You receive an error message stating "Runtime error 6" when you attempt to use online Help.

Intercepts type-checking code and ignores the type check function. Some Visual Basic applications attempt to store 32-bit handles in a 16-bit variable, which works in Windows 95 and Windows 98, because most handles use only the lower 16 bits of that handle. However, in Windows NT and later operating systems, the handles often use the upper 16 bits of the handle.

LUARedirectReg

Executable programs designed to run at Windows Startup, such as application toolbars, do not run for all users.

Redirects the placement of registry entries to the HKEY_CURRENT_USER subtree if the application does not have the correct permissions to write to the intended subtree.

MoveIniToRegistry

You cannot apply a default screensaver.

Moves INI data into the registry.

See Also

Concepts

Known Compatibility Fixes, Compatibility Modes, and AppHelp Messages
Internet Explorer Compatibility Test Tool