[KingJ]

I assume you are talking about the new IRC plugin released. This was compiled against the .NET Framework 3.5 x86, so you need to ensure that's installed. Even if you have another version of the .NET framework installed (e.g 1.1, 2.0, 3.0) you must install 3.5 for this to work. You can find it on http://download.microsoft.com