A problem in rendering has arisen on all my files?

Question

The red line in timeline will not render when Enter is keyed. The WAB brackets are in place at the beginning 00:00:00:02 and end  00:01:22:18 of the clip. The WAB areais a consistent grey. I tried renderng thru' the share tab and when idicated as a PC file it did show a processing bar to 100%.. But the original clip was unchanged : red bar .  I checked other files but they all had the same sympton - red bar would not render. As a result I cannot export my files to an .avi format since the export function is "greyed out".
I then tried to re-install my Version 9 disk. No change.    
My o/s is Windows 7. If you need pc system details let me know.
Anybody able to answer this question.
Thanks Rtay2799

Answer 1

Thank you all who responded.
VDO Surfer: I've tried closing and reopening project and then tried to render. No change.
It appears that something is stopping the rendering process, since if you hold down the Enter key, you can see the dialog box fluttering on and off on the screen, ie. the progress bar showing % complete and estimated time to complete. But it won't initiate the process.
I also went to timeline-> Delete Rendered files. But it did not render when Enter is keyed.
Lastly I looked at the Media cache by Edit->Preferences-> ScratchDisks but following the path mentioned in the Media Cache didn't find the file to delete. The path was C:\Users\richard\appdata\roaming\adobe\common\. I tried changing the button labeled Custom to other options Same as Project and My Documents but this caued no change.
Steve: I understand what you are saying about Share, but I only tried that since it at least showed a progress bar of rendering. As noted above, nothing will initiate the rendering by the Enter key or the Timeline -> Render work areas.
I'm also puzzled by the File-> Export function being "greyed out". will the options be available once the timeline bar turns green?
I was not aware that the project settings were for miniDV. The footage in the clip I am trying to render comes from my Nikon P6000 set in the video mode rather than taking single digital  images. I transfered the video clips direct from the camera to my computer via USB cable, they are listed as an .avi file not .mov as previously indicated. I use a Panasonic AGDVC30 as my regular camcorder.
I mentioned that I recently installed Verson 9 of PREL and wondered if using the newer version on a previous file done on Version 7 may be a problem. But only some of my files have the rendering problem, others render from red to green correctly when changes are made.
I hope all this gives you something to chew on... I'm not sure what the next steps should be?
Richard (Rtay2799)