(I originally posted this in the vista installation/setup discussion, which I
think is the incorrect discussion)

I've been fighting this for weeks (maybe months?!) and several programs won't
install because of it.

Several programs (Dynamics NAV, Jet Reports, others) seems to require MSXML4
to function and I must have a corrupted install. I've spent tons of time
researching this and it seems this is a known problem and I've seen several
recommendations on fixing it: disable anti-virus/spysweeper, uninstall MSXML4
and re-install (it's not in my list of programs/features or program updates
so I can't un-install).

I think my issue might be slightly different. I downloaded MSXML.MSI
manually and when I use verbose logging, the install fails he

MSI (s) (28:F4) [18:37:29:850]: Executing op: SetTargetFolder(Folder=C:\SXS\)
MSI (s) (28:F4) [18:37:29:850]: Executing op: SetSourceFolder(Folder=1\SXS\)
MSI (s) (28:F4) [18:37:29:850]: Executing op:
AssemblyCopy(SourceName=msxml4.dll,SourceCabKey=ms xml4.dll.sxs.2E8D8EBB_CC16_45E1_BBCA_CB1ED881EDB7, DestName=msxml4.dll,Attributes=512,FileSize=123392 0,PerTick=32768,,VerifyMedia=1,,,,,ComponentId={30 3994BA-6487-47AE-AF1D-7AF6088EEBDB},,,,AssemblyMode=0,)
MSI (s) (28:F4) [18:37:29:851]: Assembly Error:The system cannot find the
path specified.

MSI (s) (28:F4) [18:37:29:851]: Note: 1: 1935 2:
{303994BA-6487-47AE-AF1D-7AF6088EEBDB} 3: 0x80070003 4: IAssemblyCache 5:
CreateAssemblyCacheItem 6:
Microsoft.MSXML2,publicKeyToken="6bd6b9abf345378f" ,version="4.20.9818.0",type="win32",processorArchi tecture="x86"
MSI (s) (28:F4) [18:37:29:851]: Assembly Error (sxs): To get more diagnostic
information, enable the Component Based Servicing Log.
Error 1935. An error occured during the installation of assembly component
{303994BA-6487-47AE-AF1D-7AF6088EEBDB}. HRESULT: 0x80070003. assembly
interface: IAssemblyCache, function: CreateAssemblyCacheItem, assembly name:
Microsoft.MSXML2,publicKeyToken="6bd6b9abf345378f" ,version="4.20.9818.0",type="win32",processorArchi tecture="x86"
MSI (s) (28:F4) [18:37:33:310]: Product: MSXML 4.0 SP2 Parser and SDK --
Error 1935. An error occured during the installation of assembly component
{303994BA-6487-47AE-AF1D-7AF6088EEBDB}. HRESULT: 0x80070003. assembly
interface: IAssemblyCache, function: CreateAssemblyCacheItem, assembly name:
Microsoft.MSXML2,publicKeyToken="6bd6b9abf345378f" ,version="4.20.9818.0",type="win32",processorArchi tecture="x86"

The weird thing I see is the "C:\SXS" target path...that path doesn't exist
(my research tells me that's the side-by-side dll install folder for multiple
version). I believe the correct path should be "C:\windows\winsxs" (which
seems to be protected by the system and can be only written to by installers
that are signed or something).

I'm completely stuck, I have no idea what to do to fix this.