Can't add arrowhead to stroke

When I create a line segment, and go to the Stroke menu and click arrowheads to pick one to apply to the path, I get empty dropdown menus (both in the start and end sides). All other stroke options are working fine.

I suspect this is a plug-in problem. I looked in my files and have, in my Plug-ins Folder:

Illustrator Filters/AddArrow.aip

Illustrator UI/AddArrowUI.aip

The last one includes:

/Contents/MacOS/AddArrowUI

/Contents/Resources/AddArrowUI.rsrc

Any help would be very appreciated, I use this tool frequently and in this new computer at work am having this problem.

Regards