Adobe Reader Version 2015.008.20082 Note: McAfee Security is offered in the download.

What version of Adobe Reader do you have? For example, the new "DC" version, Reader XI, Reader X?

On the Add-ons page, Plugins section, the plugin usually is called Adobe Acrobat and if it's disabled (set to "Never Activate") it should appear at the bottom of the list on a grayed background.

If it's not there, a number of different things could be happening, including:

• Problems related to the Adobe Reader installer
  • File is actually missing
  • Registry entry that points Firefox to the file is missing

• Problems related to Firefox processing the information
  • Firefox set not to check the Registry for plugins
  • Firefox's plugin database corrupted

Next steps would depend on what version you have.