Trouble Updating - can't open pdf file
 

I have been trying to update LimeWire for my IMac (OS 8.6). I downloaded the info from the webpage, and it shows up on my desktop as a pdf file. When I try to open it, Adobe Acrobat 4.0 opens. An error message then appears on my screen reading, "There was an error opening this document. File does not begin with '%PDF-'. " Is there any way that I can get around this? Am I doing something wrong? If you have any more questions or comments, feel free to respond to me via email at marsha_99@yahoo.com. Thanks!!
-Marsha Peterson