What can cause a pdf to print the wrong characters. The PDF can be viewed fine but prints with the character set off by 1 character so a web site "www.ncbg.unc.edu" becomes "xxx/odcd/vod/f ev"  This happens to some but not all PDFs and they have been downloaded from any number of web sites. They open fine online and on the PC, Iit's only a problem when printing which is on a Dell 1710 laser printer. The system is a Dell Latitude D420 running XP and Adobe reader 9.1 with the latest print driver.

Any suggestions? Thanks