AppCompatCache

[Poolsharkzz]

Could you folks look more into this?

 

Is there something CCleaner cleaner can do about this?

 

Sorry for being a pain,

 

poolsharkzz

 

 

*****

 

Here's one of the more amazing (and stupid) registry entries in XP:

 

HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\Session Manager\AppCompatibility

 

Look at the AppCompatCache Value. It's more than 150K of garbage! And what's more, it is loaded into kernel memory and I have yet to find where it is used!

 

XP will not boot if the AppCompatCache value is not there. So here's what you do. Delete the value, then re-create it with a one-byte binary entry of 0. XP will now boot fine and everything will be as before...except you have removed 50K from the registry and from kernel memory!

 

If you make the same change in all the ControlSet00x branches, you can remove 450K+ from both the registry and system memory.

[mike20021969]

On 27/10/2008 at 23:05, Poolsharkzz said:

Delete the value, then re-create it with a one-byte binary entry of 0. XP will now boot fine and everything will be as before...except you have removed 50K from the registry and from kernel memory!

If you make the same change in all the ControlSet00x branches, you can remove 450K+ from both the registry and system memory.

Sorry for dragging this old thread back up, but the method doesn't work.

The new value simply gets re-written with all the previous data (probably what was stored in memory from previous boot up).

Question: So does anyone know if it's possible to clear the data in the AppCompatCache value and "start from scratch" as it contains lots of "history" of previous executables.

[Andavari]

Look in the community winapp2.ini file (look for the URL link at the bottom of the first post on the very first page). Then in winapp2.ini either loaded in your web browser or the file you've downloaded look for the cleaner in it named exactly this (use search function):
[Session Manager *]

It doesn't clear it out completely only selected parts are cleaned, and also some physical files on the hard disk.

[mike20021969]

[Session Manager *]
LangSecRef=3025
Detect=HKLM\Software\Microsoft\Windows
Default=False
FileKey1=%WinDir%\AppCompat\Programs|*.txt;*.xml
FileKey2=%WinDir%\AppCompat\Programs\Install|*.txt;*.xml
RegKey1=HKLM\System\CurrentControlSet\Control\Session Manager\AppCompatCache|AppCompatCache
RegKey2=HKLM\System\CurrentControlSet\Control\Session Manager\AppCompatCache|CacheMainSdb
RegKey3=HKLM\System\CurrentControlSet\Control\Session Manager\AppCompatCache|SdbTime

 

HKLM\System\CurrentControlSet\Control\Session Manager\AppCompatCache doesn't exist on Windows XP.

HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\Session Manager\AppCompatibility is the value under which the AppCompatCache key is stored (duplicated also at HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\Control\Session Manager\AppCompatibility & HKEY_LOCAL_MACHINE\SYSTEM\ControlSet003\Control\Session Manager\AppCompatibility).

[Andavari]

Who knows for sure which exact version of Windows its intended for.

On my WinXP system it's a value listed as AppCompatCache housed inside three areas, all the same exact size too when exported:
HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\Control\Session Manager\AppCompatibility
HKEY_LOCAL_MACHINE\SYSTEM\ControlSet002\Control\Session Manager\AppCompatibility
HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\Session Manager\AppCompatibility

I don't know if it's safe to clean though.

[mike20021969]

Still not sure if it's possible to completely clean that Key then.

Thanks anyway.