A Hobart A200 stand mixer that I cannot get the dough hook off of?

I had the same problem too. There should be maybe 1/4" of loose vertical play of the dough hook (or similar attachment) on the agitator shaft. The hook locks in place rotationally on the shaft until it is pushed up. Before you try to turn the dough hook backwards in an attempt to remove it, push it upwards and hold it up, then rotate.

replace the speed select switch

Check with your local Hobart office.
www.hobartservice.com Click on "Locate an Office" and enter your Zip.

A 20 qt "E" dough arm is S-23467. A 12 qt is S-62886.
A 20 qt "S" sweet dough beater is R-8022.

Check your recipe against the capacity chart found here: http://www.primasupply.com/images/hobarta200.pdf

You may be overloading the unit. Hope this helps.

You have killed it by overloading the bowl. Hobart recomends no more than 65% bowl capacity on doughs & 75% on batters or icings. Replace the motor or the whole unit

In what speed is it slipping?You only use 1st speed for dough,right?Can you put it in gear and stop the hook from moving with your hand?Let me know.

The bowl holds 20 quarts--are you overloading the mix?This mixer is not made for medium/heavy pizza dough.Depending on the pounds of dough,water and other ingredients will affect the mixer in some way.

Check the planetary.this is the bottom part of the mixer where you attach the hook.
You will see two nuts; make sure their tight as the planetary may have moved down.
Also have a look below:
http://cgi.ebay.com/HOBART-A200-20-QUART-MIXER-SERVICE-PARTS-MANUAL_W0QQitemZ160203114233QQcmdZViewItem

amy, depending on how old your mixer is there are 2 types of clutches for 1st gear.these could be your problems--a key is sheared on the shaft--shaft/gear is broken.the bottom part of the mixer where you put on the attachements is called the planetary,does it look like it has moved down?you could tell if the dough hook,wire whip,ect,ect is hitting the bottom of the bowl.if this is the case its just simply tightening the 2 nuts next to the beater shaft.if this is not the case you would have to dissasemble the transmission.let me know.