I've been working on a 15 minute short film over the past few weeks, in Premiere and After Effects. I seem to have ammased 134GB worth of Render files in the directory: Library/ Application Support/ Adobe/ Common/ Media Cache Files (despite having all my scratch disks set to the external hard drive).
If I delete all these files, and reopen Premiere then presumably I'll have a lot of rendering to do again, but also presumably I'll have significantly less data in this folder - freeing up my struggling laptop a bit! - Also I have already cleanded the cache in Premiere preferences - freed up about 20GB.
Basically I'm worried that I'm going to damage my project in some way, as I still have a lot more work to do on it - but I've got to get this folder size down.
So, you did what it says in http://forums.adobe.com/thread/1007934?tstart=0 ?
I know of no reason not to delete temporary files (other than the time it will take to recreate any needed files)
It's important to note that Cache and Scratch are two different things, often stored in two different locations. Either can be safely deleted without 'harming' your project, however any necessary Cache files will be rebuilt upon opening that project, and you may have to wait some time for that to happen.
Preview (scratch) files can also be redone manually, but again, you will wait for that render time.