macro

I have bought a 70-300 Tamron lens for my D3100.It seems very nice but I cannot use the macro setting. There are no instructions.Any ideas

Where did you buy the lens from? I would suggest you get the model number and google "model number manual". I am sure you will find something out there on the interweb. But be careful, it's a dangerous place man....

Are you trying to get too close ? Closest distance you can achieve is 0.95mtr but you have to be in the 180-300mm range for that distance