PPro CS4 won't render my sequence

Everytime I send a sequence to Media Encoder, it just sits there. And sits and sits, etc. At the bottom it just says "Loading "Gleaner_Shoot.prproj".

I'm using a 2008 Mac with 8 cores with 16 gigs of ram.

My footage came from the Canon HV20. I have clips at both 24p and 1080i.

I'm setting up my sequences to match the clips I'm placing in them.

One thing of note is I'm really only using 3 looong clips. Since CS4 doesn't do scene detection well. I opted to instead make subclips from the long clips and use those. 2 of them are about 30 minutes long and one is nearly an hour. Could this be the problem?

Thing is, this happens even when I do a 1-minute sequence test.

It even happens when I try to use a test sequence which contains only audio.

I've tried outputting to quicktime and MPEG 2. I was careful to set the export settings to match the sources.

After a long wait, Media Encoder gives up and I get a warning icon in the status column. It says this:


- Source File: /Users/johnstanowski/Library/Caches/TemporaryItems/Gleaner_Shoot.prproj
- Output File: /Users/johnstanowski/Desktop/THURDAY.mov
- Preset Used: Custom
- Video:
- Audio:
- Bitrate:
- Encoding Time: 00:11:07
Tue Aug 4 13:19:39 2009 : Encoding Failed
-----------------------------------------------------------------------------
Could not read from the source. Please check if it has moved or been deleted.
-----------------------------------------------------------------------------"


I usually use After Effects so I'm not really up on Premiere that much, but I've used it a good bit in the past and never came across this problem.

Any ideas?

P.S. I just closed the whole project and started a new one with simple DV footage... and the same thing is happening. I'm beginning to think there's a plugin or something messing with Premiere Pro. I think it's a plugin because this problem is happening here at work and also at home.