Welcome to the community.
AutoCAD 2013 is only compatible with Windows 8 after installing SP2. Please find and download the appropriate service pack here:
Hopefully that will get you up and running.
Unhandled access and unhandled exception errors can be caused my many different factors. Please try the below solutions, they are the are the most common solutions for this kind of error
1.) Update your video driver to the latest version available from your video card manufacturer.
2.)In your programs and features control panel repair your installation of microsoft .net framework 4.0
3.) Uninstall all versions of Microsoft Visual C++ and re-install them. I have provided links below
Microsoft Visual C++ 2005 SP1 Redistributable Package (x86)
Microsoft Visual C++ 2005 SP1 Redistributable Package (x64)
Microsoft Visual C++ 2008 SP1 Redistributable Package (x86)
Microsoft Visual C++ 2008 SP1 Redistributable Package (x64)
Microsoft Visual C++ 2010 SP1 Redistributable Package (x86)
Microsoft Visual C++ 2010 SP1 Redistributable Package (x64)
It's possible that you have some .NET Framework issues. This is a common side-effect. If repairing or reinstalling it does not work, you can try the cleanup tool.
.NET Framework issues can be resolved using the .NET Framework Cleanup Tool. More information about this tool can be found at my discussion thread here:
Thank you for your answers, i tried everything and it helped a little bit, the programm starts now, but gets then the another error.
And iam also not sure if i fixxed the .net issue correctly. I tried it with .net framwork cleanup and used it, but after the framework was still installed und i couldnt reinstall. Is there a way to just deinstall it?
Sorry I just noticed you are on windows 8. In that case .net framework is a "Feature" of windows. You can turn the feature on and off by checking and unchecking the box but I don't thnik it accomplishes the same thing as an uninstall/reinstall. The .net framework repair tool is your best bet.
I'm sorry to say I am not sure what else might be occuring here. If you need to get something done in CAD immediatly I would suggest installing the 30 day trial of AutoCAD 2014.
It was designed to support windows 8 so you are less likely to encounter any problems. If you continue to have problems with even that version it may be time to consider a windows OS re-installation.
the problem is, that i need the programm for my university and there we work with 2013. I dont how how equal the both programms are! are there big differences?