constant error '-9129' after 9.0.3 upgrade

[gthrasher]

I've recently upgraded from 9.0.2 LE to 9.0.3 LE on Win7.
Ever since the upgrade to 9.0.3, I've been getting error -9129 when working with sessions.

9.0.2 didn't throw this error (with the same sessions i'm working with now).

I have my H/W buffer set to the max (1024).
Pro Tools is the only program running on my computer at the time.
I have quad core CPU (shows as 8 CPUs to the OS), and 16 GB RAM, so shouldn't be a problem with available resources on my machine.

Has anyone else seen anything like this? Any ideas on how to get around this (without downgrading back to 9.0.2)?

thank you