A new version of adobe reader has just been released to patch some security issues. The .MSI (Microsoft installer file) file version is 41 meg, the usual .exe that adobe wants you to download will be even bigger. I'm not saying that is what your download is, but its a good candidate. I was going to say that 50 meg sounds a little big for an MSI definitions file, but the one I have saved to disk is almost 56 megs. Keep in mind though that is a stand alone definitions file with every definition up to the date I downloaded it on. Not the sequential update you get once or twice a day though windows update. These days there are so many programs that want to phone home to auto update etc, its hard to know whats going in and out of your internet pipe some times.