pdfsaver.exe, and it's process, PDF-XChange Drivers Helper, have not been tested thoroughly enough yet to state definitely if they are harmful or not. Has pdfsaver.exe been found or your machine? If you know what this file does, please post a comment with what you know.

Malware and spyware can infect your machine very easily, even if you only surf the internet.

The best way to avoid problems with malware and other types of malware is to scan your machine for free and get rid of all the harmful files right now.