LotRO uses Microsoft .Net 1.1. This is an ancient fossil of a framework and is not supported by Windows 8 AT ALL. But there is a workaround.
First, you need to download (but not run!) the dotnetfx available from the link you will be sent to when your launcher crashes. Yay! Fun stuff! Without running it, only because it will save you time because it won't even attempt to install, you need to unpack the file you downloaded with Winrar. Another program might work but I know Winrar will because I have done this before for other issues in other versions of Windows. Once you unpack it, you will have a couple of files. You want to then run netfx.msi (if you don't have file extensions on, it has an icon with a computer and a disc on it - not any of the ones with a yellow box). This will fully install .Net 1.1 on Windows 8 and allow LotRO to run.
If anyone from Turbine sees this, you might want to think about upgrading the framework you use. As more people migrate to Windows 8, they might not want to be bothered with all this and you will start losing people because they can't even get past the launcher.
First, you need to download (but not run!) the dotnetfx available from the link you will be sent to when your launcher crashes. Yay! Fun stuff! Without running it, only because it will save you time because it won't even attempt to install, you need to unpack the file you downloaded with Winrar. Another program might work but I know Winrar will because I have done this before for other issues in other versions of Windows. Once you unpack it, you will have a couple of files. You want to then run netfx.msi (if you don't have file extensions on, it has an icon with a computer and a disc on it - not any of the ones with a yellow box). This will fully install .Net 1.1 on Windows 8 and allow LotRO to run.
If anyone from Turbine sees this, you might want to think about upgrading the framework you use. As more people migrate to Windows 8, they might not want to be bothered with all this and you will start losing people because they can't even get past the launcher.