On Mon, Sep 28, 2009 at 12:32 PM, Joseph Heaton <[email protected]> wrote: > The c:\windows\installer folder. On the system I'm looking at it is a hidden > system folder. Does anyone know the function of this folder, and whether or > not the contents can be cleared?
That folder is part of the -- wait for it -- Windows Installer. (Also called "Microsoft Installer" or MSI.) The folder gets used to store a number of things, including database information about installed packages, cached patches for (re)installation, program icons (stored as .EXE files), temporary files during install, and other mysterious stuff. It typically uses opaque IDs rather than human-readable names. It's your classic Microsoft big-ball-of-mud. You don't want to go "pruning" in there without specific direction. If you remove a file related to a currently-installed package, then future attempts at upgrading, repairing, or removing that package may fail. For example, patches are cached so they can be re-applied or reversed during future operations, and database info tells MSI exactly what to do during an uninstall. However, it is also quite possible for stale files to accumulate in there. Unfortunately, since it's a rather opaque data store, it's hard to know what's needed and what isn't. The MSIZAP utility has a command, G, to "remove orphaned cached Windows Installer data files". Exactly how it determines what an orphan is, I don't know, but it's supposedly safe as long as you don't use the "!" modifier to force things. I don't know if it's comprehensive -- I don't know if "MSIZAP G" will find all possible stale/orphan files. I suspect not. The other options in MSIZAP generally remove information from the MSI store without actually touching package files on your system. In other words, indiscriminate use of MSIZAP will just remove the *record* of an install, not the install itself. You have been warned. The MSIZAP tool comes with the "Windows Installer Cleanup Utility". You can get it from MSKB 290301. -- Ben ~ Finally, powerful endpoint security that ISN'T a resource hog! ~ ~ <http://www.sunbeltsoftware.com/Business/VIPRE-Enterprise/> ~
