Welcome to the forum.
This behavior often happens when the Render files are moved, deleted, or PrE just loses track of them. For the first two, the user has most often done this, but it could be an issue with one's HDD. For the latter, I'm not sure why/how this happens, but sometimes it does. Same with PrPro, which has no background Rendering.
Now, both ATR and Steve Grisetti, two constant contributors to this forum, have extensive experience in PrE 8 and might have some ideas, or observations on what is happening in your two Projects and may have a fix.
Thank you for listing the problem Assets, as that helps a great deal. I am surprised that the Titles are in that group, as they are created in PrE and stored in the .PREL (Project) file. I am less surprised that an MPEG file is one of the faulting ones, but it still should not happen this way - once Rendered, those Render files should be made available to PrE, when you Open up the Project.
Have you gotten any messages, requesting the location of any Render files (will have a long, rather cryptic name), when you Open one of these Projects? When one has moved, or deleted, the Render files, this is normally what PrE will do - ask where the missing Render files are located, and the user can just navigate to that folder.
Sorry I cannot be of more help,
Again, no consolation, but it seems that there are certain circumstances where PrPro CS4 also looses the Render files - and the CFA (Conformed Audio) and PEK (Waveform Display) files. For many, the various outlined Adobe KB Articles outling cures, do not seem to help. Maybe PrE 8 has inherited some of this. Let us hope not, and that it is really a simple fix with just a switch, or similar.
Hunt, did you see that, in the Muvipix discussion, Robert traced this problem to bugs in the current version of Quicktime? When he rolled back to an earlier version, the problem went away!
I did not. Thank you.
I've been seeing a lot of issues with many Adobe programs and the QT Player 7.6.x versions - far too many. I am still on 7.5.5, and most have reported success by rolling-back to that version, which seems to be the last good version.
Same was true with the 7.4.x versions. Most found that 7.3.5 was good with Adobe, until 7.5.5 came out.
Interesting, and your comment is appreciated. I will point this out on the PrPro forum. It might well help others with similar problems.
Thanks very much for your responses. Hunt, in answer to your question - I'm not being prompted to locate the files when I start Premiere and I'm not manually deleting or modifying them between sessions. I can fully render the movie, save, close, immediately re-open and the clips are back to having red lines and background rendering starts running. Additionally the problem has gone from bad to worse! I originally reported it was just a few specific clips on each movie that had the problem. However, it's now happening to any clip I make a change to. I've clicked Timeline->Delete Rendered Files so that it will completely re-render the whole movie from scratch, so I'll let you know how that goes. If not, I'll try manually deleting the contents of the Media Cache Files directory. If not, I guess it's worth trying a re-install of PRE8 (Like I've got nothing better to do...!).
Thanks again to you both,
Each time I reinstall Premiere Elements 8, I get additional problems. My version of the aforementioned problem is as follows. I drag a clip into the sceneline. Background rendering commences and proceeds to 100%. Then, although I have no other software running and have not even touched the keyboard, rendering begins again, goes to 100% and begins again, indefinitely.
Before you do a reinstall, did not notice Steve G's comments on QT Player 7.6.x? What version of QT Player do you have installed?
If you have one of the 7.6.x series, maybe try 7.5.5 (perviously known good version with Adobe software).
I was indeed using QuickTime 7.6.x. I've uninstalled it, but it has not helped. I've also, as mentioned above, used the option to clear the cached files from within Adobe, manually deleted the media cache and manually deleted the Preview Files of one of the projects. All of this was done seperately and test inbetween. None have helped.
Additionally, I just tried to get into Organiser and it won't start. It just bings and then brings up the 'Crash Report' screen (Which I'd bet money that they don't read - I've submitted about 30 since buying Premier Elements a couple of weeks ago). So, Organiser won't start at all any more (I've tried launching it from within Premiere Elements and from the popup launcher, and yes, I've tried rebooting). Also, the program crashes pretty much every single day that I use it, for one reason or other. Usually I'm just using it for an hour or two in the evening. Over the weekend, I used it for a number of hours but had a number of crashes. I'd say it's crashing on about a 2 hour basis.
I apologise if this is coming over a bit negative, particularly as I'm in an Adobe forum and am writing something thats going to be read by Adobe fans. However, I came into this pretty provider neutral. I choose Adobe because it has a good brand name and based on the brief demo'ing I did of it's product and a couple of rivals. I am pretty shocked with what I've found. Premeiere Elements 8 comes across as unfinished. It's clearly bug ridden - intermittently crashing on a 2 hour basis, and some functions (Organiser, saving rendered files) completely not functioning. I admit I'm working with AVCHD files, which are relatively new, but in that case Adobe shouldn't have released the product until it was up to the task. Then there are lots of areas that simply seem like they need a bit more polish - not being able to type directory names in when creating/importing/exporting files, but having to go through the click, click, click file tree explorer for example.
Anyway, sorry to rant. I've just started uninstalling, so I'll see how things are after I've re-installed. If not, I'm pretty close to asking for a refund or simply writing this purchase off. I've been told that Final Cut Express is very good and I've wanted an excuse to 'need' a Mac for a while, so perhaps this is the push I wanted?!
Thanks for your help, I'll post an update just to let you know if the re-install solves the problem, but I don't expect any further troubleshooting - unless it's from an Adobe developer and he wants to personally apologise to me!
I was also facing this issue so found a simple workaround for this. Just hit enter once you reopen the project to render the timeline and save the project once. (Since only a small part of the timeline was RED when i opened my project so it took quite a less time to render the remaining part.) Once I did manual rendering and saved my project, the problem didn't reappear.
Hope this helps you too