This problem cropped up today, after updating my eVGA motherboard's chipset in order to try and fix an unrelated issue. After installing the chipset update (contained SATA and Ethernet drivers), every time I've tried to start my Ubuntu VM, it reaches 95% in the web interface and then just hangs.
I'm using VMWare Server 2.0.2, running it within Windows 7 64-bit. I haven't had any issues up until now, and I suspect it has something to do with the chipset update. I've already tried reinstalling VMWare itself, removing the VM from the inventory and re-adding it, and neither has proved successful. I'm also not sure how to kill the VMware server process itself once the start-up hangs; I've only been able to try again by rebooting (as none of the VMWare Services listed kill the server process itself).
Edit: Uhhh...as an addendum: I have a cron job set up on my Ubuntu VM that runs every 20 minutes. The VM is still listed in the VMWare web interface as at 95% of startup, and the start/stop buttons are still disabled, but the cronjob just ran. I also tested SSH, and I was able to tunnel into the Ubuntu VM as well. Now I'm really confused.
Edit #2: I just started a thread on the VMWare Server support forums on this same topic. Hopefully between the two communities, we can come up with an answer:
Edit #3: In lieu of a specific fix, I've switched over to VirtualBox, and all is working just fine.