Unresponsive keys on HP12C

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Using the 'P' key, 'C' key turn the key to the PROG position, PRESS the 0 (zero) key and then 0 (zero). At this point, press the key of the item that you wish to change or Enter the PLU # and press the PLU Key. If the description of the item is ok then press 'cash/enter' and then press it again. You should be on the PRICE/Halo line, Change the amount to the correct amount and press cash/enter at this point you can then press the clear key and then turn the key to the 'REG' Position. Press the Key of the item you changed and it should display the new price.

I HAVE BOUGHT A USED ER5200M. I HAVE CLEARD THE PLU'S AND RE PROGRAMMD WITH MY ITEM & PRICE INTO THE PLU'S. EACH NIGHT AFTER I DO "Z" REPORT, THE REGISTER IS STILL TOTALING MY GRAND TOTAL ONTO THE OTHER OWNERS GRAND TOTAL WITH MINE, HOW DO I CLEAR GRAND TOTAL SO IT WILL BE ONLY MY GRAND TOTAL ?

To switch the radix mark, turn the calculator off, press and hold the decimal point key, press the ON key, then release both keys.

It could be some dirt or grit in the keyboard, which a blast or two of compressed air might clear out. It could be a worn dome on the inside of the keyboard.
If you want to have it repaired, there's FixThatCalc, though they're currently not taking new orders. There also have been several threads on opening and cleaning Voyager series keyboards at the Museum of HP Calculators. Here's one article on opening a Voyager.

I tried your suggested fix Electroboy and all it did was print out some end of year totals or something that used about 5 metres of paper, I managed to get help from the Hotpos tech support guys and they gave me this sequence which immediately fixed the problem......
Turn key to program
Press
3
subtotal
1
0
0
0
0
0
cash
subtotal
Turn key back to reg
That's it :)

To access the Toshiba recovery partition, power off the laptop. Hold down the 0 (zero) key and turn the laptop on. Keep holding down the zero key until the TOSHIBA logo appears, where you should start tapping the zero key repeatedly. Stop if the unit beeps or when the TOSHIBA logo disappears. The screen should flash ** HDD RECOVERY MODE ** for a split second, then load the Toshiba recovery program right from the hard drive.

Note that this erases all data, and reloads all factory default software. Be sure to back up all your important personal data beforehand!

To switch the radix point between the US and European modes, press and hold the decimal point key, press and release the ON key, then release the decimal point key.

ya...mine does too. the last software fix in Aug was SUPPOSED to fix the issue, but i think it made it worse.....you can try to reset the phone....you just might have too much info on it.

now careful, cause a master reset on this phone, will delete everything on the device, so back everything up first.

go to MENU > SETTINGS > PHONE SETTINGS > RESET > RESET ALL SETTINGS

***default code is by default 000000 (6 zeros)***

good luck :)

BT Freelance XD 5500

Resetting the base & handset/s on a BT Freelance XD5500:

Hold the Find button on the base unit until you get a double beep then
tap the Find button 7 times.
On the handset:
remove a battery
hold the menu key and refit the battery
screen says SW VERSION
press up arrow key until screen shows REGISTER CLEAR
press menu
press menu again and wait for OK to appear
remove a battery and refit

Registering the XD5500 handset.
Then register the handset to the base as follows:
Hold Find button on base unit until you get two beeps
On handset:
Press menu
Scroll to register
Press menu
Scroll to Register Base
Press menu
Press 1
Wait
When it says PIN ? Enter 0 0 0 0 (four zeros) and press menu.

Note:
If you have more than one handset then repeat registering the handset to the base for each subsequent handset/phone.


If this procedure fails to solve the issue, then you have a unit with a
fault and if it is less than a year since purchase the retailer should
change it for you.