Radi Atanassov

SharePoint MCM, MVP, MCT and owner of OneBit Software

Silverlight install errors and changing the default Program Files location (NOT SharePoint)

I was having problems installing both Flash and Silverlight on a new build, and thought I might share my situation.

I have an SSD drive (C:\)and another 7200 RPM mechanical HDD (D:\). I did quite a bit reading on how to optimize my SSD’s lifetime, and many sources say that we shouldn’t worry about taking much care of our SSD’s. They live longer now + mine has a 3 year warranty. I still wanted to implement some tweaks, and I also wanted to place some rarely used program files on my mechanical drive. Things I did: Move page file to D: (and reduce it as I have 16GB RAM), put browser and Windows temp files on D:, set download folder to D:, and some others which I don’t recall anymore (: Many might ask why, but that is for another discussion.

The challenge I was having is setting Program Files to default on D:. I did not do this during the installation of Windows 7, and I couldn’t find a “supported” way change from C: to D:, so I went ahead and changed the registry key, expecting something to fail at one point in time. Everything seems fine and it has been 2 months and I have passed many installations, but the first things that failed we’re Flash and Silverlight. Both addons gave meaningless error messages.

Reg Key: HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\ProgramFilesDir AND \ProgramFilesDir (x86)

The fix is easy, change the registry key back to C:, restart, install them and return it to D: I want it to stay D: so it is the default when installing applications. Note, I actually had to restart, but you could probably get away with log off/log on.

So to close this off, changing the default program files directory is not supported, it may be fine at first, but you might get nasty errors later on. Plan this during the installation of Windows 7, rather than forget like me.

And just as a side note, I’ve always been a fan of hacking and customizing my OS… I have done various other things to it, some I understand, but some that I don’t and shouldn’t do. I installed some Lenovo software/drivers, then decided to modify my start button and chrome, and now Windows 7 thinks it’s not genuine and it keeps reminding me! I can live with that (I probably have 3 Windows 7 licenses and 1 laptop), but it should stick as a warning to everyone (: