All of a sudden I can't open pdf files in Firefox. IE works ok but not Firefox. I suspect it's a Reader X (10.x.x.x) issue. I tried to go back to 9.4 but have been unable to do so. Can anyone tell me how to get back to 9.4. I tried following the instructions on the Adobe website but they didn't work as the downloaded file is blocked - either because Adobe 10 is already there or, after uninstalling 10, the install fails because there is no file to "update" - even though I downloaded 9.4, which was not identified as an update..
The latest version of Firefox doesn't support Adobe Reader 9. If you want to use an old version of Adobe Reader, you should be able to bypass this by navigating to about:config and changing the key extensions.checkCompatibility to false.
Hope that helps!