Cheers,
While trying to install the Hexxit Mod per the Technic Launcher, following problem occured (as seen on the picture):
http://www.pic-upload.de/view-29417405/TechnicIssue.jpg.html
After I tried to uninstall and reinstall the launcher as well as Minecraft itself the same error still occured.
If any more information are needed, feel free to ask.
Greets