So you have a PC, phone, access point, or printer which is connected to the wall jack but the connection is not activated for some reason… IT’S DEAD. When you check the switch port, it doesn’t show a link light, nor does the network adapter. This is typically called a Dead Drop.
Dead Drops are often simple problems that occur when a connection is not patched through to the wall jack. In many businesses, only those connections that are actively being used are patched. When offices or meeting rooms are moved around, sometimes the network jacks are not tested for the new users, or drops that are intentionally left disconnected may not be properly documented. Additionally, the switch port may be administratively disabled.
When any devices have been physically moved in the office, be sure to test the new connections to ensure they are working properly. In the case of an IP Phone, it is possible that power is not being sufficiently supplied to the phone by your PoE switch or power brick.