ERR: "This installation package could not be opened."

ERROR: "This installation package could not be opened. Conact the application vendor to verify that this is a valid Windows Installer package."

Environment: Windows Server 2003 SP1 (Fully updated)
Active Directory Enabled
Domain Controller Enabled
Software is 100% Legit and activated

This error keeps popping up on MSI files. I can install any EXE installer fine (logged in as administrator, full rights) With 2003 SP1 Installer 3.1 is automatically installed so I cannot upgrade. I tried a CLI

msiexec /regserver
msiexec /a c:\temp\php5.msi (i tried renaming it)

I've stopped and restarted the service, rebooted, reinstalled SP1 and the problem keeps reoccuring. I know the file is good, I downloaded it from PHP.net off both mirrors and tried both inside the c:\temp folder as well as from the desktop.

I'm pulling my hair out here, a simple upgrade from PHP4.4.4 to 5.2 is driving me insane. All of this because I installed MySQL5 and PHP4.4.4 cant authenticate to MySQL.

Anyone experience this? I find references all over for this string but most of it is in lists of error codes, which isnt helping me much.

 

Just a followup, I am getting this in a logfile
--------------
DEBUG: Error 2219: Database: . Invalid Installer database format
1: 2219 2: 3: 4:
This installation package could not be opened. Contact the application vendor to verify that this is a valid Windows Installer package.
C:\DOCUME~1\ADMINI~1\LOCALS~1\Temp\221bcf.msi
MSI (c) (A0:A8) [23:11:32:859]: Product: -- Installation failed.
---------------

The file 2221bcf.msi is a randomly generated filename (I tried looking for the file and placing the msi in a file with the same name but each time I run the installer that filename changes)

This particular file is PHP5.2 , I'm pretty sure it is a good installer file or it would be all over the place and fixed pretty fast. The same error pops up on every MSI file regardless of vendor or source.

 

Administrator Edit: Please start your own thread giving details of the issues you are experiencing. Do not hijack another member's thread. Thanks