AVG Firewall Letdown

After spending all day yesterday reinstalling my sister's PC I thought that I was almost done when I posted yesterday's entry. However, AVG's Firewall fell over and wouldn't restart. I spent a further 3 hours trying to sort it last night and a further 2 hours this morning. I tried everything I could think of and read a lot of the AVG forums, with no success, before biting the bullet and wiping the PC to begin again. I've reinstalled everything again today and it's behaving fine. It's in the spare room defragging the drives before I hand it back tomorrow.