Serial ports(in 1.0.5 & Port in 1.6.11) is greyed out under tools I am running a linux distro on my pc(Ubuntu 16.04). I have installed Arduino IDE(version 1.0.5 since it's the only one available on the store) from the Ubuntu Software Center and also using the .ZIP file from the official Arduino website(version 1.6.11). When I ran IDE(1.0.5) the "Serial Port" drop-down was greyed out. Next ran the IDE(1.6.11) and again the "Port" drop-down under Tools was greyed out. I have spent hours looking online for a solution but all in vain. A tried and tested working solution will be highly appreciated.
Information on a “Serial Port Setup” page at fedorahosted.org should be adequate to sort the problem manually.  Here are a few snippets from that page, along with notes about application to the current problem.

• Use command ls -l /dev/ttyUSB* to find out the serial port's group.  For example, on my Ubuntu system that shows

crw-rw---- 1 root dialout 188, 0 Aug 20 11:13 /dev/ttyUSB0


Note, substitute for ttyUSB if the port you're concerned about doesn't start with that.

• Use command groups to find out which groups you belong to.

• The fedorahosted page says to use command sudo adduser (username) dialout to add dialout to your groups list.  I haven't tried that approach, and would be more inclined to instead try sudo usermod -a -G dialout (username) [where  “(username)” represents your username].