For me its the CD Burning wizard, how unreliable it can be, one minute it works, the next its a complete disaster.
I burnt some files on my PC at home, (which has a DVD/CD-RW Drive), carried it to work, when I open the CD-RW on my computer work, the files I burnt at home were not there. How frustrating this was for me.
I ensure that both PC’s burn at the same speed, but I still get the same issue. Both computers are Dells, so why can’t they corporate? Many times I have erased the disk to start a clean slate, but the problem still persist, and files that I was sure I had erased still end up reappearing after I thought I had erased them a long time ago.
This is one feature I would love for Microsoft to offer an update for, because it is so inconsistent and it makes damn angry!