OK, how many times have you done this? Windows Update notifies you that an update is ready to install. You select yes to install it, but then when it is done it says it needs to restart your system.
“Not now!” you say, “I am a busy and important person! I will get to your silly restart in my own good time.”
Fast forward a day, a couple days, etc. You are a developer. Time to test an installation. Hmmm. something failed. Hmmm… what could be going wrong? Try many silly things. This thing worked last time I tried it. Obscur error message from ODBC. Google search. How could I possibly have incompatible versions of MDAC on my machine. Start to download latest version of MDAC.
Bing! light bulb goes on. Didn’t I forget to do a restart after a windows update last night? Restart. Problem dissappears.
Oh well, I didn’t really want to do anything more productive with those last couple hours anyway.