Yes,I understand the problem is recent.Check for plugin updates here.May be your plugin is out of date.

Open the Adobe Reader program and make sure that "Display PDF in browser" is selected in the Adobe Reader program preferences, under "Internet". If it is already selected, "toggle" the setting as follows:

In Adobe Reader, choose "Edit -> Preferences -> Internet". Deselect "Display PDF In Browser" and then click OK. Choose "Edit -> Preferences -> Internet" Select "Display PDF In Browser" and then click OK. Reopen your Mozilla application and verify that the plugin is enabled.

hraxx said

Click on document

Have you tried a right click?

You might already have checked this, but just in case...

When you install Firefox, it defaults to displaying PDFs in an internal viewer. If you haven't already, you will need to change that on the Options page using the steps in this article: View PDF files in Firefox or choose another viewer. (Note: it is important to filter the use using PDF and not looking for Adobe.)

If you made that change before, try choosing a different option such as opening in Adobe Reader (outside of Firefox) and test that. If it works, then try changing it back to using the Adobe Acrobat plugin (inside of Firefox).

Any improvement?

hraxx said

Click on document on web and it does not appera - nothing happens. In Internet Explorer, no problem. Tried " about:plugins" and found Adobe PDF Plugin for Firefox 15.8.20082. I believe this is VERY RECENT PROBLEM

thanks toall of you.Problem solved