Hmm. No idea, sorry. Generic errors like that are always hard to troubleshoot...
You might want to check out the Revora forums; given the fact they manage multiplayer for the post-RA2 games nowadays, they probably have experience with these games' problems on the newest systems.
[edit]
Wait, it could just be the settings thing... did you also check out the "Common Issues and Solutions" thread? It's another sticky thread at the top of the forum.
Go to your My Documents folder and check whether there's a "Command and Conquer Generals Data" and "Command and Conquer Generals Zero Hour Data" folder in it. If not, create them.
Inside that folder, you should have a file called "options.ini". One of the most common problems with Generals is that this file is missing. If it is, create it by right clicking, selecting "new" -> "Text Document", and then renaming it from "New Text Document.txt" to "options.ini". If you don't see the .txt in the suggested filename, make sure to enable extensions in Windows; otherwise you won't ever be able to rename it to .ini.
The contents to put into that file are listed in the aforementioned common issues thread. Search for "Generals load crashes" on the page.
