Mainboard error Just on startup it's say "Loading OS failed".What to do? I had format internal memory.I only can open USB mode(SEQ+Exit) and Format internal memory(Combi+Exit).When formating complet,I trying to enter new system(from Korg site) with USB mode.Always same situation,"Loading OS failed".Help (KORG M50 61)

For the best answer contact Korg customer service. Here's the link-
http://www.korg.com/us/support/contact

do you want to sell the old main board?

If you can get to a formatting function do that. The memory contents have to follow a certain format as a self check it does when starting and they are corrupted now, probably random data. You might try the procedure that is used on another Zoom product for clearing the memory... Hold down the store button while turning on the power... then possibly pressing the store once again... worth a try.

It MAY be waiting for an UPDATE of firmware via USB. In other words you may have triggered an update mode that it will not exit without sending an update. The second possibility that comes to mind is that one of the buttons or the switch behind it may be stuck which can lock up the processor. Look for a button stuck in or that feels un-normal.

If you are being asked to reload the OS, you will have to do that. SOME devices have trouble with USB sticks that are larger than some limit... that may or may not be specified. If you haven't tried reloading, try it with a USB stick no greater than 1GB... yes they are getting hard to find that small.

It will require repair. I suspect by you description that the D-A convertor has failed. This is a chip that is far beyond a DIY project to change. Do further testing to make sure the power supply voltages are correct and that headphone output sounds the same problem.

Here is your service manual: http://elektrotanya.com/korg_pa800_sm.pdf/download.html

Scroll down to "get manual" and click to download the manual. IGNORE other download links.

from the akai forums:


to set the os back to factory settings press and hold the erase key till the mpc has booted to the main screen.

to erase the harddisk goto either the load or save screen and then choose utility - there you will find the option to format the hdd.

you can also format the drive (or any inserted compact flash-card) from your computer thru the usb connection, but it is recommended to use the internal format because the mpc can be a little picky when you format it from the outside.

at first i would check if there is any folder or the internal memory is set to autoload and just turn that of or point it to another folder of you choice. that way you can keep the factory delivered sounds. maybe you want to use them later, even if it is just to explore the mpc. the factory sounds can be also downloaded later, but be advised that there are different iterations of the stock sounds, depending on whether your mpc shiped with a 32 or 128mb compact flash card.

also the mpc os is not on the harddrive but in the internal memory. to check the version hit mode-> pad10. latest official version is os 1.24. if your main srceen looks different than in the manual check double and triple before you do anything, because the previous owner might have installed the third party jj os which comes in different versions. some of them cost a lot of money! if you find this check the other forum here for the alternative os.

There are many ways to attempt a fix with this error you could try firsta boot into safe mode then running msconfig

select the diagnostic startup then reboot in the normal way this might enable you to find your error.

If this fails click the LAUNCH SYSTEM RESTORE which maybe able to use one of your restore points created at an earlier time (usually before an app install) this may give you the fix you require.

http://safemanuals.com/user-guide-instructions-owner-manual/AKAI/MPC2500-_E This is a free download. Try pages 14 and 15 also 23 also44 also page 66 also 83 also 90(purge samples) 103 (memory cards) 11 formatting page 108 deleting data in memory before loading, I'd suggest page 112 (save the contents by backing up to computer) then wiping the memory card. I don't have one of these units and I see the hard drive is an option which I don't know if you have. Read the manual from beginning top end and always save your work before deleting anything. Hope this helps.