Open Run (Windows Key+R)
Type in %appdata% and hit ok
Open .technic, find the Hexxit folder
Make a backup of all your single player saves and delete the folder.
Then relaunch the modpack AMD it should redownload it
Well no need to be get defensive. I have no idea what category this is in because I'm using tapatalk. Your the first post I've come across thats not a 'Cry for help' or off topic random thread.
Are you making any changes to the files other then Server.properties?
Try resetting the pack from the client side. I doubt its the server since this is directly from technic.
If you can do this. You can build a pc.
Windows 8 will have no issue runnig you apps and games. Older games that came out during the time of XP will need go be patched to at least Vista.
I dont think Optifine is installed.. the Video Settings should be present. Just without the AA and AF I believe. But definitely a majority of Optifine Ultra's settings. The version doesn't affect installation steps so you must have did something wrong.