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I'm using ESET Smart Security 4 on Windows 7.

I selected Interactive Mode so it asks me when something needs to connect to my PC. So when I was installing a game named League of Legends, I was away from my computer. When I came back, I saw that the download was finished but ESET was asking whether to allow .NET Runtime Optimization Service to connect my computer using port 80 TCP.

So I selected Allow but It was too late because the download was already finished.

I can play the game, but could it be bugged or broken or something?

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So, I still don't understand your question. Is the game working? Do you experience any real issues? – slhck Apr 15 '12 at 10:46

It should not be a problem, though the game may run (or start up) a little slower.

The .NET Runtime Optimization Service is part of the .NET Native Image Generator. It's supposed to compile the .NET CLI to a computer specific binary image.

The Native Image Generator (Ngen.exe) is a tool that improves the performance of managed applications. Ngen.exe creates native images, which are files containing compiled processor-specific machine code, and installs them into the native image cache on the local computer. The runtime can use native images from the cache instead of using the just-in-time (JIT) compiler to compile the original assembly.

When the native image is incompatible or not available, the .NET framework is supposed to fall back to JIT compilation. So, it should still work and may be a little slower, though it may not affect it at all. I'm not sure exactly why the Native Image Generator needs internet access, however.

The native image service is a Windows service that generates and maintains native images. The native image service allows the developer to defer the installation and update of native images to periods when the computer is idle.

On Windows Vista, the name displayed for the native image service is "Microsoft.NET Framework NGEN v2.0.50727_X86" or "Microsoft.NET Framework NGEN v2.0.50727_X64". On all earlier versions of Microsoft Windows, the name is ".NET Runtime Optimization Service v2.0.50727_X86" or ".NET Runtime Optimization Service v2.0.50727_X64".

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