I have Edit/Preferences/Options/Display PDF in Browser unchecked in Adbove Acrobat Reader 5.0.5. IE6 correctly starts the PDF outside the browser, but Mozilla always starts it within the browser.
try to remove the 'nppdf32.dll' from your plugin folder of 6.x installation and restart the browser. Automatically, the helper app should be picked up and you should be able to launch acrobat externally. Gabor, pls let me know if this works.
Shrirang, Thanks, the workaround makes the PDF file display outside the browser. But than maybe there are users who would want to have both options ... (and it to be controlled within the Adobe settings?)
if users want either to work, then you can use the 'helper app' setting inside Preferences ( to launch the app externally or choose the plugin). The browser supports this...