Grind size too big even when it is set to finest

Generally, this is not a problem with the machine but with how you're loading the coffee! Sounds typical of one of these problems:-

Not enough coffee in the basket
Coffee should be filled and tamped to about 3mm below the rim.
Coffee grind not fine enough (too coarse)
Do you grind your own coffee or buy ready-ground? If buying ready-ground, make sure it is for espresso (fine) and not for filter or plunger.
If you have your own grinder, (like the Sunbeam Conical Grinder), then make sure the coffee hopper on top is securely connected to the grinder. I'd been using mine for years on the the finest grind (1) not realising the hopper wan't on right. Only discovered it when I took it apart to clean. Now my grinder is on 9-10 to grind for espresso.
Coffee not tampered down hard enough
You do need to provide a reasonable degree of pressure to tamp he coffee down just right.
Group head not turned tight enough
Push the group handle as far to the right as it will go, then ease it back just a fraction to have the right pressure.

Generally, this is not a problem with the machine but with how you're loading the coffee! Sounds typical of one of these problems:-

Not enough coffee in the basket
Coffee should be filled and tamped to about 3mm below the rim.
Coffee grind not fine enough (too coarse)
Do you grind your own coffee or buy ready-ground? If buying ready-ground, make sure it is for espresso (fine) and not for filter or plunger.
If you have your own grinder, (like the Sunbeam Conical Grinder), then make sure the coffee hopper on top is securely connected to the grinder. I'd been using mine for years on the the finest grind (1) not realising the hopper wan't on right. Only discovered it when I took it apart to clean. Now my grinder is on 9-10 to grind for espresso.
Coffee not tampered down hard enough
You do need to provide a reasonable degree of pressure to tamp the coffee down just right.
Group head not turned tight enough
Push the group handle as far to the right as it will go, then ease it back just a fraction to have the right pressure.

Grind Adjustment Tools required: Large blade and medium Phillips head screwdrivers In order to adjust the grind, follow these steps (Refer to figure A): 1. Remove all coffee from the hopper. 2. Set selector knob to the finest setting (Espresso or Turkish) depending on the model. 3. Loosen both knob retainer screws in selector knob one turn only. 4. While pressing the bag switch, located behind the spout, press the START button so that the grinder will run during adjustment. 810 model - Press the ON or START button so that the grinder will run during adjustment. 5. With the grinder still running, turn the adjusting screw in the center of the selector knob slowly to the right until a slight clicking noise is heard. Immediately turn the adjusting screw to the left one grind setting. This is the finest grind obtainable. 6. Tighten both of the knob retainer screws. Once the ESPRESSO grind has been set (Turkish for Model 835, 875, 890), the other grind settings will automatically set correctly. 7. Press the STOP or OFF button. IMPORTANT: Always be sure the grinding burrs are not touching while the machine is running on the ESPRESSO/TURKISH setting. Otherwise serious damage to the motor may result.

To adjust this grinder turn the adjustment nob to the finest setting (ESPRESSO or TURKISH) Locate 2 small set screws on the adjusting nob. Loosen these screws (do not remove them) about one full turn. Start the grinder and, with it running, VERY SLOWLY and GRADUALLY, turn the CENTER adjustment screw clockwise until you begin to hear the burrs begin to touch (whirring sound). Back off the center screw about 1/16 of a turn, shut of grinder and re-tighten the set screws. Then try the grind on DRIP or there about for brewed coffee.

Hi Your burr is not locked in. You need to remove the beans from the hopper. Remove the hopper. Remove the burr. Turn the grinder upside down over the trash can. Put the burr back in only make sure that the burr is down. Install the bean hopper and when you turn the bean hopper it should move the burr. Then you can adjust your grind. Make sure that the grinder is running is your going to a finer grind or you could break the grinder. You can turn it to a coarse grind any time.

This model grinder won't do espresso. There is a DIY mod available online that involves disassembling the machine, and recalibrating the burrs to produce a finer grind. I did it on mine, it was definitely better, but it's not going to get you to the coveted 30 second pull for your espresso. Search on Starbucks Barista Grinder Mod. It is a great grinder otherwise, very reliable.

Hi
Your grinder adjustment ring inside has its tabs broken. Contact Baratza at 877-701-2021 and they should be able to help get a new one.

I have a Zass and sometimes have a problem with it self adjusting, but when I do need to adjust it, I find that I have give it a good tap on the top to make sure it adjusts. So, just turn the knob counter clockwise as far as it will go, then give it a good knock on the top and bottom and try again. My mill offers the full grinding range, from a fine powder to large chunks.

Hi,

Loosen the screw in the bean hopper and take it off, set the adjustment to "8" and put it back again and try to grind finer.

1 would be the finest. I wouldn't recommend going under 2 though.

You risk clogging your grinder and machine under 2. There's also a dosage control when you open the door on the side. + means a bigger dosage or puck.

Hope this helps.