First time on new Mac tower, keep getting "Unable to render: Codec not found. You may be using..." error

So based on the purchase recommendations of the fine folks here at LAFCUPG, I just bought/set up my new Mac tower:

Processor Name: 6-Core Intel Xeon
Processor Speed: 3.33 GHz
Number Of Processors: 1
Total Number Of Cores: 6
Memory: 6 GB
ATI Radeon HD 5870

I reinstalled FCP (7.0.3) and wanted to try it out on new machine so I converted a short .m4v clip to Apple Pro Res 422 (HQ) using MPEG Streamclip, loaded it into FCP then put a couple snippets on a timeline.

So far, no problem.

However, when I add a cross dissolve between the clips and try to render, I keep getting the same error message: Codec not found. You may be using a compression type w/out the corresponding hardware card.

Since I had this problem once before on my old computer, someone here had said maybe I had a corrupted sequence so I started over again (re-converted the clip, opened a new project in FCP, etc.). While that worked last time, this time keep getting the same error message.

I next trashed my pref files but, alas, to no avail.

Thus, does anyone have any suggestions? So frustrating not to be able to do anything on FCP with my new system. @#$%!

Thanks!

Eric

Corrupted preferences? Something else?
Create New User with Admin status. Create project in that account and try to do the dissolve and see what happens. If it's a user preference issue it should be fine in the New User. If it's a system issue it'll likely continue to happen.

What's not clear is what clips are you dissolving between. Two Pro Res Clips? Pro Res and something else?

Craig,

First, thanks for getting back to me. I'm not a pro so things like this drive me to drink! @#$%

As for the clips I'm dissolving between, it's two smaller clips both from the same Pro Res master clip. They were the first two I put on the timeline (this was just a practice project to try out the new system).

If you create a new sequence and drop one of the clips in do you get a pop up box asking you to match sequence settings? If so, check yes, and try in that sequence.

I'm wondering if somehow you have the timeline setup to a video card that might not be installed with the new Mac. In other words, it's trying to render the dissolve using a hardware card codec that's not there. Doing the above might work.

Please try creating the new user with admin status and trying there as I mentioned above. That will avert any user related preferences that might have run amuck.

Craig,

First off, THANK YOU. Like I said, I'm not a pro so I know just enough to not be able to fix this problem. Thus, I sincerely appreciate your time.

Yes, when I create a new sequence I do get that pop up and I have been pressing yes. But to no avail (just tried it yet again).

I'm using this card: ATI Radeon HD 5870

And just now tried creating a New User w/ Admin acct but, alas, same problem.

Solved, Craig.

Apparently something in the clip itself was changing the sequence settings so that the video processing settings were switched to 10-bit YUV rather than 8-bit YUV when it rendered.

My long editing nightmare is now over.

Thank you once again for your time. Sincerely appreciated.