Hi i am having an issue with some of my pdf files where i cant highlight text or use the find tool to look for certain words. It seems that the difference between files that will allow this and the ones that won't is the PDF version and PDF producer, even so it should work anyway i assume. Does anyone know what could be wrong?
You can try this totally free PDF-XCHANGE VIEWER , it allow some basic editing on pdf files including highlighting the text of pdf files.
Hope it can do you some favor.
May be that this are scans.