Had err message so I changed the batteries. The monitor tries to build up the pressure stop and goes on again. The result reading is at the low 100. My BP is usually in the mid 120.

SOURCE: husky comp on 1st start builds up 75 lbs and wont restart

Check the reset button on the motor to see if it tripped. The motor may be overheating. Some motors have an internal breaker and they have to cool off before they restart. Also check the pressure switch. Move the switch back and forth ( on and off ) and listen for a click. If it doesn't click with low to no air pressure then the switch is bad.

SOURCE: I just changed the oil

ok this can be done 2 different ways 1 , with the radio controls , should be in the owners manual , or the easier way , to reset the oil maintinence light , turn the key to the ON position , engine OFF , depress the gas pedal to the floor 3 times within 5 seconds and it will reset ,

now the tire monitor system , same deal should be in the owners manual , and done with the radio controls , or the easier way , turn key to ON position , engine OFF , cycle the parking lights 3 times within 5 seconds , (turn on - turn off = 1 cycle)

pretty cool huh? but make sure your tires were properly inflated before you reset the tire monitoring system .

SOURCE: Sony ICD-P210, ERR ACCESS message

Your problem may have been caused when you removed the unit from the PC without using the "safely remove hardware" option.
What you need to do is download the latest version of Digital Voice Editor (I think we are up to 3.1 now)
When you connect the ICD unit it will probably give you a number of access errors
Ignore them and go to the IC Recorder Menu. Select WHOLE and DELETE. Delete everything.
After a minute or so the unit will come to life and you'll see the Directories that are standard in your unit.
Remove the hardware from the computer (safely! by closing the program first) and turn the unit off.
Now turn it on...... Bingo!

SOURCE: err 3 is displayed

Wrist blood pressure monitors must be used with the arm above heart level. You can do the pledge of allegiance while doing a reading to make sure this is done. Usually this error occurs when inflation takes too long or the placement of cuff is wrong.

SOURCE: screen shows ERR. I changed batteries and tried

You're right..This happens often when one changes the battery.Here's what to do :
The ERR message can only be corrected by holding in the DISP/MENU and STOP buttons for two seconds, which results in ALL the material on the recorder being erased. It will say (FOR) for a few minutes while it is erasing everything, then will work again.
Solution found at http://www.amazon.co.uk/Olympus-VN-2100-Digital-Recorder-microphone/dp/B000V3NTEU