New Dell PC. New ISP logged on to outlook express and yahoo. Somehow in the process my internet explorer has vanished. How do I get it back. I downloaded a PC doctor who gave me the following errors. Missing files c:\Windows\System32\hlinkprx.dll; Invalid Active X\com file; invalid active x\com Subsection file; invalid application path; invalid microsoft shared file; invalid uninstall information. Can you help me. I'm not pc literate.