I downloaded Adobe 7 Reader and it worked OK. I then used it to open some PDF Files on a site I use for business. When I did this their site gave me a warning message 'Error 372...PDF.OCX may be outdated'.
I contacted the business and they did not have a clue as to the cause!
I then uninstalled Adobe 7, an re-installed Adobe 6. Visited the same again and no problem, could view the files OK.