Attention everyone! A recent security patch on Windows 7 means that you may find Civ4 vanilla and Warlords no longer start. The security patch comes with a recent batch of Windows updates, and it disables the service that verifies your dvd is genuine. Apparently security issues have been discovered with the service. The issue doesn't affect BtS (because BtS doesn't try to verify the dvd), and it won't affect you if you're using Steam (because - obviously - no dvd!). If you want to know the gory technical details: Discussion on civfanatics here Details of the workaround here (Microsoft knowledge base article), and here (myonlinesecurity.co.uk article). (Thanks to High King J.J. for tracking down those links). If you just want a quick fix: To fix the issue, you'll need to temporarily re-enable the service just before you start civ. 1. Start the command prompt as an administrator. To do this, click the Windows button and type cmd in the textbox at the bottom. Then - this is important - hit CTRL + SHIFT + ENTER. (Don't just hit Enter, as that won't run as an administrator). You'll see the command prompt window - a black window that let's you type in commands. 2. In this window type in the following two commands - on each one hit enter, and then wait for the command to complete (a few seconds). Code: sc config secdrv start= demand sc start secdrv You'll now be able to start Civ. Note the spaces are important in these commands. 3. Once civ has started, you really ought to stop the service (because it has a security vulnerability - although it won't stop civ working if you don't do this). To do this, in the same window type Code: sc stop secdrv Unfortunately you'll need to do this every time you start civ (if you don't bother stopping the service, you won't need to do it again until you reboot your computer). As an alternative to step 2, if you want an easy life, you can type in Code: sc config secdrv start= auto sc start secdrv This should set the service back to how it was before the security patch - always running so you'll always be able to start Civ in the future without going through this annoying procedure (until MS disable it again, which I wouldn't be surprised if they do). However, this isn't recommended due to the service having a security vulnerability.