How can you erase Android os off tablet and reinstall a new os using a computer or micro SD card

What new OS?

If you mean a new version of Android, then just use the menu to check for updates. If you mean a custom build of android you will need to unlock the bootloader, install a custom recovery and use that to install the custom android ROM. Whether you can do this will depend on what tablet you have (can it be unlocked, is there a custom recovery or ROM for it?).

If you mean an operating system other than android, forget it.

 

That's not how it works. If the bootloader is locked down enough you can't do that, and if not in most cases you need to enable unlocking from the tablet first. And if there is no custom software for that model you are stuck (the OS has to be built for the specific model: there is no such thing as a generic build you can install on any mobile device).

From what you say though custom software may not be needed. Reflashing with manufacturer stock software may suffice. But that also depends on what tablet it is.

So either way nobody can help without knowing what tablet it is & what OS version.

 

Why is the tablet locked to begin with?

 

Is this about one of those Jpay prison issued locked tablets? We've been getting a few posts about them quite recently

 

Just looking up JPay online, it's a privately owned, for-profit service and its tablets are highly curated with restrictions on functionality. They're by design meant to provide only limited tasks that they manage.
https://www.motherjones.com/politics/2018/10/tablets-prisons-inmates-jpay-securus-global-tel-link/
https://en.wikipedia.org/wiki/JPay
If you really want to flash a new, clean Android ROM onto it, you're going to have to obtain one from JPay which doesn't seem likely given that making ROMs for their tablets open to the public would be something that opens up a big hole in their business model.

 

Not only their business model, if these secure JP5 tablets were cracked. I think that would cause a serious security issue for the prison authorities, with inmates installing VPNs, encrypted messaging apps etc.

 

"windroid"? Do you mean nandroid? To do that you'd need a custom recovery like TWRP specifically developed and built for the JP5. And before that you'd need to find a way into the thing, to bypass its security features. Good luck with that.

 

The bottom line is these tablets don't appear to be the best option for hacking. If you're doing this to achieve some goal that's a different matter but if you just want a tablet to delve into and experiment with, take a look at swappa.com. They sell pre-owned and refurbished mobile devices, there are some really good bargains for old, brand name tablets:
https://swappa.com/buy/tablets

 

If both had the same custom recovery installed you could create a nandroid backup of the ROM of one of them and load it on the other. But you need to be able to unlock them both and install a custom recovery (which must be built for that particular model) - if there is no unlock mechanism for this model or nobody has built such a recovery this is not an option. And this only copies the ROM, if anything is locked down at a deeper level than that a nandroid won't help.

Erasing the bootloader would hard brick the device. Fortunately unless you can unlock the bootloader first there is no way of erasing it.

 

It's ancient, and no longer supported. Even when it was new it relied on manufacturer unlocks for many devices.

Basically you can try it, but don't get your hopes up. And unless there are custom recoveries and ROMs for this device it won't be able to do what to OP wants anyway.

 

What if I'm on a jp5 with apps using wifi from a cellphone how can I restore my messenger app I deleted by moving to fast also give me all the protocol I need to convert a jp5 into a android with any apps

 

Not going to happen, dude.

 

Please send me the link to restore my apps I uninstalled on jp5 by mista