That being said this part is very important if the red x is driving you nuts.
Samsung galaxy tab charge red x.
The red x will only appear if the charging voltage is less than 5 3v.
The device then does not charge because of the low power or amperage of the charger.
Quick charger compatible samsung galaxy tab s4 10 5 2018 tab a 10 1 2019 tab a 10 5 tab s5e tab s3 9 7 tablet charging cord ul listed extra long 6 6 ft cord adaptive fast charge black 3 9 out of 5 stars 107.
Get it as soon as tue sep 22.
Samsung based tablets detect if the charger is a original charger and if not limits the chargers power and displays the not charging icon or the battery icon with the red x.
All computers usb ports are regulated at 5 0v.
When i connect my charging cable i hear charging sound but with this x mark it is not charging.
I had the red x problem with my tab 12 2 even though i was using original correct 5 3 volt charger and cable compared to galaxy note 4 s 5 0 volt charger.
Samsung galaxy tab 1 2 3 10 1 a e etc if you are having a hard time with your samsung galaxy tab you should read this blog post.
If you unplug the tablet from the pc or the charger and the red x was present the red x will go away because no chargers are being detected.
The solution that worked for me.