I have files that say they are missing or offline. I have checked all my folders off of lightroom and they can not be found. I have used the ? mark settings to find and still not found. I can see the images on lightroom so they have to be in my system some how. How can I retrieve these images? Is there a re boot for lightroom? Need help ASAP!
Your files are not actually "in" Lightroom. They are on your hard drive(s) and just referenced by Lightroom.
Associated with the catalog are a ton of "LrPrev" preview files, which is what LR is showing you.
There is no way to simply get images out of the preview cache. However, someone may know of a plug-in or utility that can do so.