I have an UN55ES8000F Samsung TV with vertical lines on the screen too. Place the TV on a table with the back of the TV up. Open the back of the TV. You will see three main boards. One is the mother board, in my case the mother board was in the left of the TV looking from the back. The other is the power supply board which is located on the right side. The third one is called T-con board and is located on the center bottom of the screen. Some TVs got them on the top. This Tcon board has three connectors. One connector on the top, which connects the Tcon board to the mother board. The other two connectors are on the bottom of the board and they connect the Tcon board to the screen. Both of these connectors are identical. One is for the left side of the screen and the other is for the right side of the screen. Disconnect the two ribbons from the Tcon board and from the screen and clean then with an eraser and then spray them with contact cleaner. Do one at a time so you can remember how the go together. Be very careful when disconnecting the ribbon from the Tcon board and from the screen. The connectors have a small black tab on top. Lift these tabs away from the ribbon toward the board and slide the ribbon out. To reinsert the ribbon, slide the ribbon in and lower the black tap to hold the ribbon in place. The ribbons have a black mark on them, make sure these black marks are right in line with the black tap once these tabs are press against the ribbon. This should eliminate your vertical lines. It worked for me. I also recommend that you disconnect and connect all other connectors on the boards.