There are a couple of things to check first off that don't require test equipment. One being to make certain you are dealing with the same type of fiber. Be certain that the patch cords and the fiber are both multi or single mode. Then be certain what the switch requires. They have to be the same.
Second, be certain you can get light through the fiber links. Try lighting a fiber strand from the closet at one end with a flashlight (actually, there are adapters made for this) and see if you can see the flash of light at the other end. DO NOT TRY THIS WITH THE EQUIPMENT PLUGGED INTO THE FIBER! If the equipment uses a laser to light the fiber, you can permanently damage your eyes.
If you can see light, then you need to call in someone with fiber test equipment like a light meter and/or an OTDR to test the fiber.
It is possible that the patch cords you are using on the LC links are doing a double roll. You have to connect the transmit fiber at one end to the receive at the other. Sometimes the fiber is rolled at the interconnect cabinet, sometimes with the patch cord. If your fiber is being rolled twice, then your equipment is trying to transmit both directions on the same strand and the other end can't "see" what the other is sending.