How do i take the er-apoo off my sharp stereo

See page 176 of user manual
cas_man_ERA410_ERA420.pdf (sharpusa.com)

If problem not solved then master reset the machine using procedure given Chapter 1 (Master Reset)
Sharp ER-A410, ER-A420 (SERV.MAN4) Service Manual - FREE DOWNLOAD ' ERA410 420 Programming Manual (servicemanuals.us)

Since they do not repair these decks due to the cost of new being so low you might as well buy one.

Je viens de recevoir un code d'erreur ER-APOO, comment puis-je le r?parer pour pouvoir continuer ? utiliser mon syst?me comme d'habitude

USA and Canada version Sharp ER-A570 User manual:http://the-checkout-tech.com/manuals/cashregisters/Sharp_ER-A570_and_ER-A610_operation_CANADA_manual.html

Europe/ Pacific version Sharp ER-A570 user manual:http://the-checkout-tech.com/manuals/cashregisters/Sharp_ER-A570_instruction_manual.html

USA and Canada version Sharp ER-A570 programming manual:http://the-checkout-tech.com/manuals/cashregisters/Sharp_ER-A570_programming_A_ver_manual.html

Europe/ Pacific version Sharp ER-A570 programming manual:http://the-checkout-tech.com/manuals/cashregisters/Sharp_ER-A570_programming_manual.html

http://www.helpowl.com/p/Sharp/ER-A330/76005

The letter H appears in the screen. The register will not respond. Any idea to what the Letter H means?

Programming Manual: http://www.nodevice.com/user_manual/sharp/cash_registers/er-a440.html

You need the PC Link software for your model.
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All of these manuals can be downloaded at:
http://the-checkout-tech.com/

sharp ER-1017 Service
sharp ER-1072 Service
sharp ER-1073 Service
sharp ER-1074 Service
sharp ER-1075 Service
sharp ER-1076 User Service
sharp ER-1077 Service Programming
sharp ER-1077
sharp ER-1077
sharp ER-1772 Service
sharp ER-1772s Service
sharp ER-1871 Service
sharp ER-1872 Service
sharp ER-1873 User Service
sharp ER-1875 User Service
sharp ER-1910 User Service
sharp ER-1911 User Service Programming
sharp ER-1911s User Programming
sharp ER-1920 User Service
sharp ER-1921 User(R) Service Programming
sharp ER-1921s Programming
sharp ER-1970 User Service Programming
sharp ER-2000U Service
sharp ER-2100 User Service
sharp ER-2370 Service
sharp ER-2371 User(R) Service Programming(R)
sharp ER-2385 Service
sharp ER-2386 Service
sharp ER-2386s User
sharp ER-2395 Service
sharp ER-2396 Service
sharp ER-2720 Service
sharp ER-2722 Service
sharp ER-2722A User Service
sharp ER-2742 Service
sharp ER-2742A Service
sharp ER-2770 Service
sharp ER-2782 Service
sharp ER-2782A Service
sharp ER-2905 Service
sharp ER-2908 Service
sharp ER-2910 Service Programming
sharp ER-2970 User Service
sharp ER-2975 Service
sharp ER-2980 User Service
sharp ER-2980S Service
sharp ER-3100 User Service Programming
sharp ER-3110 User Service Programming
sharp ER-3115 Service Programming
sharp ER-3120 User Service Programming
sharp ER-3550 Service
sharp ER-3600 User Service
sharp ER-3630 User Service
sharp ER-3712 User Service
sharp ER-3721 Service
sharp ER-3731 Service
sharp ER-3732 User Service
sharp ER-4100 User Service Programming(R)
sharp ER-4110 User Service Programming(R)
sharp ER-4100S Service
sharp ER-4110S Service
sharp ER-4550 Service
sharp ER-4630 User Service
sharp ER-4633 Service
sharp ER-4700 User
sharp ER-6740 Service
sharp ER-8700 Not Available, do you want to swap?
sharp ER-A150 User Service Programming
sharp ER-A160 User Service Programming
sharp ER-A170 User(R) Service Programming
sharp ER-A180 User Service Programming
sharp ER-A220 User Service Programming
sharp ER-A227G Programming
sharp ER-A250 User Service Programming
sharp ER-A310 User Service Programming
sharp ER-A320 User Programming
sharp ER-A330 User Service Programming
sharp ER-A410 User Service Programming
sharp ER-A420 User Service Programming
sharp ER-A430 User Service Programming
sharp ER-A440 User Service Programming
sharp ER-A440S Programming
sharp ER-A450 User Programming
sharp ER-A450S User Service Programming
sharp ER-A450T User Service Programming
sharp ER-A460 User Service Programming
sharp ER-A470 User Service Programming
sharp ER-A490 User(R) Service Programming
sharp ER-A510 User Service Programming
sharp ER-A510s Service
sharp ER-A520 User Service Programming
sharp ER-A530 User Service Programming
sharp ER-A550 User Service Programming
sharp ER-A550s User(R) Service
sharp ER-A570 User Service Programming
sharp ER-A610 User Service Programming
sharp ER-A650 User Service Programming
sharp ER-A650S Programming
sharp ER-A670 Not Available, do you want to swap?
sharp ER-A670S Programming
sharp ER-A750 User Service Programming
sharp ER-A770 User Service Programming
sharp ER-A770II User
sharp ER-A770M User Service
sharp ER-A771 User Service Programming
sharp ER-A850 User
sharp ER-A880 Not Available, do you want to swap?
sharp UP-3300 User Service Programming
sharp UP-3300M Service
sharp UP-3301 User Service Programming
sharp UP-600 User Service Programming
sharp UP-700 User Service Programming
sharp UP-800F User
sharp UP-810F User
sharp UP-820N User Service
sharp UP-X300 User
sharp UP-X500 User Service
sharp XE-A101 User Service Programming
sharp XE-A102 User Programming
sharp XE-A106 User
sharp XE-A110 User Service Programming
sharp XE-A120 User Service Programming
sharp XE-A130 User Service Programming
sharp XE-A201 User Service Programming
sharp XE-A202 User Service Programming
sharp XE-A203 User Programming
sharp XE-A206 User
sharp XE-A20S User Programming
sharp XE-A212 User Service Programming
sharp XE-A213 User Programming
sharp XE-A301 User Service Programming
sharp XE-A302 User Programming
sharp XE-A303 ? Programming
sharp XE-A401 User Programming
sharp XE-A402 User
sharp XE-A406 User
sharp XE-A40S User Programming
sharp XE-A505 User Programming

try to unplug wait couple minites. and turn back on. it will be ok. sometime you have to pull it out by manual. let me know.