I've been using different versions of MyDVD for years and have never had a problem.
Today I was making an ISO image file, it's for a double layer DVD just in case that matters, and kept getting this error, 8004521e, while it was doing the menus. I tried it 3 times once while the menus were still and the others while motion was applied.
I run diskeeper and spyware before every burn.
Here's my specs:
Pentium 4 2.80GHz
Hard Drive 80 GB 41.22 GB free space
Thanks in advance for any help!!!