Safest place to download SQL Server 2005 Service Pack 2 Installer I need to obtain Microsoft SQL Server 2005 Service Pack 2 as part of a rollback plan for an upgrade to SP3. All links on the Microsoft website seem to be broken. This will be installed on a very safety sensitive system and I would prefer to obtain the installer from the official Microsoft website. I am able to obtain a download link on MSDN, but it says "No product key is required" so I'm assuming it wont even give me an option to enter a license key when I install it.

Where is the safest place to obtain a Microsoft SQL Server 2005 SP2 installer (iso or exe)?
That message is simply saying you won't need to enter a product key at installation.  

The version from the MSDN downloads is the best download to use.

The SQL Server installers downloadable via MSDN subscriptions don't require at license key - the installer asks you what edition you want to install.  I'd recommend downloading the full installer for SQL Server 2005 from MSDN, installing it on a virtual machine for test purposes to see how the installer works.  The last thing you want to do is try to figure out how to install it as part of your rollback effort.