DOPO tablepowers on but has black or blank screen. tried vol and power buttons on and off but didn't work. reconnected tape thinking they were loose but didn't work tried different charger didn't work

I think it's just broken from the fall, man. It sounds like a pretty serious fall. If it's new maybe you can call the retailer to see if they can fix it for you.

use this program chines tablet software

i guess u need to hold vol+power keys for few seconds when the tablet is switched off.

My grandson forgot his password for his Nextbook Tablet, how can I unlock the screen to rest his password.

Mine was having he exact same problem. All I did was hard reset it, wipe the cache, and wipe the media partition.

First, turn off your nextbook.
Hold both the POWER button and the VOL UP button until the screen the screen comes on. Once its on, you can remove your finger from the POWER button but still keep it on the VOL UP button until the screen goes to a black BIOS screen.
From there, use the VOL DOWN button to scroll to the "Factory Reset/Wipe" option, then press POWER to enter.
Scroll down to Yes to confirm once more and that should be it for the Factory reset.
I recommend you proceed to the "Wipe cache" & "Wipe Media partition" options to be on the safe side.
I hope this solves your problem like it solved mine.

check your tab connector it may be damaged or out of place or loose, if loose it make contact with casing ,thinking is being used by an otg...hope this helps...then just follow trouble shhooting guides, holding down vol then power hold for at least 30 to 45 seconds then release power and then vol, wait about 2 mins before tab completly shuts down ...youll no longer hear the sound of a tab trying to keep running....times are approximate..if it doest help keep on reading ..eventually you'll find a few suggestions that may work together....

Important:Plug your device into power outlet

Step 1: Power off Nexus 7
Step 2: Power on while holding Volume Down/Up
(enter BootLoader)
Step 3: Press Volume Up to toggle to "Recovery Mode"then press power to select
Step 4: Hold The Power Button and tap Volume Up when you see "No Command"
Step 5: Press & hold Power Button & Volume Up Button Again
Step 6: Toggle with vol down and vol up / power at wipe data (all data) & reboot

If you cannot turn on your phone or access the phone settings, you can still perform a factory reset by using the buttons on the phone.

1. With the phone turned off, press and hold the VOLUME UP and DOWN buttons, and then briefly press the POWER button.
2. Wait for the screen to show the instructions on how to do the factory reset, and then release the VOLUME UP and DOWN buttons.
3. Follow the instructions onscreen to factory reset your phone.

Try using a paperclip to reset it on the back, hold it in for 5 seconds, if that doesnt work:
Turn the tablet all the way off, press and hold the VOL - and power at the same time for 8 to 9 seconds, it will show a green android guy with a system recovery menu. Use vol - to go down to Wipe Data/Factory Reset, press the power button to select it, go down to 'yes' to confirm, press the power button to select it, it will wipe the tablet, you then press the power button on 'reboot system'.

It is possible you got into APX mode (for transferring files with the device not in the OS using NVFlash. Great if you bricked a device). This mode is Hold VOL UP and tap POWER. In this case, you can try to use the Reset Hole on the left side of the Asus TF300 (between the microHDMI and microSD card). Try it for 3-5 seconds. Another thing you could do is hold the power button for 30 seconds, release, hold it for 3 seconds and see if it boots.

The last thing you could do is hold VOL DOWN and POWER for about 12-15 seconds until some small text appears in the top left.