Windows Installer Don'ts

Ok, so I'm a software professional (or at least I thought I was).

A few weeks back my laptop started to complain that I was running out of disk space.  I've only got 500 GB on board, and with a couple of VM's for SharePoint, SQL Server 2012, and various FOSS OSes, I really was running out of diskspace.

Know that Image of Windows Server 2003 running SQL Server 2005 and MOSS 2007?  Well that was too important to purge, so what did I do?  I dug out the handy du command and started building up a hog report.  Where was all of that space going...

• c:\MSOCache (hidden) - 2.1 GB
• c:\Windows\Installer (not hidden, but not shown either) - 17.2 GB
• c:\users\mbattey\AppData\Local\Temp (AppData hidden) - 1.85 GB
• c:\ProgramData\Microsoft (ProgramData hidden) - 4.7 GG

Hey, I'm a smart guy, right?  What the heck are all of those Windows Installer files doing still hanging around on my computer?   I'll just delete those.  MSOCache? Stupid Microsoft leaving crap everywhere.  Gone!  Temporary files?  Fried!

Ya bad idea.

Windows Update was immediately broken.  There were a handful of updates to Visual Studio (2005, 2008, 2010) waiting to be installed as well as updates for Office.  None of these would go.  Every time they ran, the MSI tool would ask for a GUID named directory off the root of one of the drive partitions, which of course didn't exist.  Trying to run a Repair from Programs and Features failed miserably with the same result.  In fact, the icons for all of the Office Documents, Adobe Reader PDFs, and a bunch of others disappeared as well.  (Methinks that Adobe and MS got lazy and weren't moving all of the DLL's out to "Program Files" like they tell everyone else to do).

So after manually removing all of the remnants from Office following a nice showcase from Microsoft (the girl reading the script sounded nice, but had trouble pronouncing RegEdit and Suite, which came out more like "reg-it" and suit), writing a custom registry cleaner to delete stuff from HKEY_LOCAL_MACHINE\SOFTWARE\Wow6432Node\Microsoft\Windows\CurrentVersion\Uninstall, HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Uninstall, and HKEY_LOCAL_MACHINE\SOFTWARE\Classes\Installer\Products, and finally correcting individual packages with MSIZap, I'm kinda sorta back to normal.

Normal as in I'm back up to all that disk use, and Office and Visual Studio will run updates, mostly.  I do highly recommend MSIZap when you've got the GUID of a a package that won't install, because it's gone missing.  It will root out all of the registry and local files related to the product and in the cases I needed it let a patch go through unperturbed.