In reply to:
www.example.com/mypdf.pdf was not working, but when I tried www.example.com/mypdf - that worked perfectly.
Hmmm... That would indicate that the name of the file on the server was mypdf, not mypdf.pdf. Perhaps it was renamed inadvertently when you uploaded it.
Anyway, I am glad you now have it worked out.
In reply to:
thanks for your time once again.
No problem, you are more than welcome. 
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